From Genghis Khan's Tomb To The Hanging Gardens Of Babylon — 9 Important Archaeological Sites That Still Haven't Been Discovered

Through the centuries, historical sites are bound to disappear. Whether due to climate change, political turmoil, or even grave robbers, there are many reasons why discoveries at notable locations are sparse, but there are still typically traces of the people and customs. Occasionally, though, it's as if they never existed to begin with...
One might believe that, in regard to important historical figures and locations, there would be some form of record, whether written or oral, that would allude to a location. However, that's not always the case...From the Hanging Gardens of Babylon to Cleopatra's tomb, here are 9 important archaeological sites that may never be found:
1.The Hanging Gardens of Babylon:
Considered one of the "Seven Wonders of the Ancient World," the Hanging Gardens of Babylon are the only Wonder that has remained elusive to archaeologists.
Most historians believe that in the sixth century BCE, King Nebuchadnezzar II had the Gardens constructed as a gift for his wife, Amytis, who was homesick for her native Media (modern-day Iran). In that day and age, it would have taken a feat of engineering to ensure the gardens were properly irrigated, leading scientists to theorize that a system akin to Roman aqueducts would have delivered water from the nearby Euphrates River to the Gardens.
While there are many descriptions of the Gardens in Greek and Roman texts, these were second-hand accounts that had been passed down throughout the centuries, as there is no mention of them in any preserved Babylonian texts. Due to the lack of archaeological evidence, some scientists assume the Gardens never truly existed. However, Oxford's Dr. Stephanie Dalley, an Assyriologist, discredited those assumptions: "That's a pretty stupid copout, really. It doesn't make sense to say we couldn't find it, so it didn't exist."
Dalley claims the lack of archaeological evidence is due, rather, to the fact that the Gardens weren't located in Babylon at all, but rather in Nineveh, the capital city of Assyria (modern-day Iraq and Turkey). She believes Assyrian king Sennacherib, not Nebuchadnezzar II, built the Gardens in the seventh century BCE, an entire century earlier than hypothesized in Babylon.
After combing through ancient texts, she noted that Sennacherib described an "unrivaled palace" in his kingdom and a "wonder for all peoples," as well as a bronze water-raising screw, which could have been used to irrigate the Gardens. Dalley explained that confusion over their location might have stemmed from the fact that after Assyria conquered Babylon in 689 BCE, Nineveh was renamed "New Babylon."
Excavations near Nineveh (near modern-day Mosul) uncovered a complex aqueduct-esque system with the inscription: "Sennacherib, king of the world…Over a great distance, I had a watercourse directed to the environs of Nineveh."
It's still unknown who or what destroyed the Gardens. Strabo's writings described "Gardens" that were in ruins by the end of the first century BCE and claimed that Alexander the Great wanted to repair them. However, the Macedonian king died before he could complete his mission, and "none of the persons who succeeded [Alexander] attended to this undertaking."
2.Genghis Khan's tomb:
Before Genghis Khan died in August 1227 CE, he requested that his grave not be marked in any way. However, this hasn't stopped a variety of individuals, from archaeologists to grave robbers, from attempting to find the ruler's final resting place, despite the fact that Marco Polo recounted that even by the late 13th century, the mystery eluded even the Mongols themselves.
Most fieldwork that has taken place to find Khan's tomb has centered around Burkhan Khaldun in northeastern Mongolia, near his birthplace. The location was even mentioned in The Secret History of the Mongols, the oldest surviving work about Khan's final days. According to the text, he declared it to be the most sacred mountain in Mongolia and said, "Bury me here when I pass away." (Historians still don't know what officially caused his demise, but one popular theory is that it was due to injuries sustained from falling off a horse in 1226). Despite this statement, archaeological searches in the area have been fruitless.
The details of Khan's burial have long been shrouded in mystery. In an oft-recounted tale, Marco Polo claimed that after 2,000 slaves finished burying Khan, they were killed by soldiers, who were in turn killed by another group of soldiers, who later killed themselves in an effort to finally secure the privacy of their revered ruler's burial site. However, this legend is not mentioned in contemporary stories.
There have also been long-standing rumors of a curse surrounding Khan's grave. In 2002 this theory recirculated after an American expedition, led by University of Chicago historian, John Woods, and former gold trader, Maury Kravitz, abruptly ended after a series of "mishaps," including workers being bitten by pit vipers (it is rumored that a two mile long wall of snakes protects the warlord's final resting place) and vehicles inexplicably rolling down hillsides.
If this didn't deter the mission, the final blow was when Mongolia's prime minister accused the team of desecrating a sacred site, stating: "I regret that our ancestors' golden tomb has been disturbed and the purity of our burial places tainted for a few dollars. This place should remain pure for the souls after death." Despite the team's theory that Khan's tomb was indeed close to their search area, Kravitz told reporters, "In each of the countries and cities and sovereign states he conquered, Genghis Khan brought back the wealth of that culture on two-wheeled wagons. Not one thing has been found. Not a single bejewelled dagger. Not a single necklace. It all went into Mongolia and never exited. (Some believe Khan's tomb contains vast quantities of treasure)."
After that trek ceased in 2002, Khan's palace was discovered by a Japanese-Mongolian expedition in October 2004, 150 miles east of Ulan Bator, which led to academic excitement that his burial site might be situated nearby. Despite this promising theory, nothing was found. There have been other expeditions since that time, but no major breakthroughs have occurred.
3.The Lost Colony of Roanoke:
One of the biggest mysteries of pre-colonial America is the fate of the Lost Colony of Roanoke. While we do know that the colony was located on present-day Roanoke Island off the coast of North Carolina, archaeologists are still unable to pinpoint the settlement's exact location and where/if the colonists resettled elsewhere. In the words of Adrian Masters, a University of Texas historian, "It's the 'Area 51' of colonial history."
The story of the Lost Colony began in 1584 when Sir Walter Raleigh sought permission from Queen Elizabeth I to establish a permanent North American settlement. She approved his request and granted permission for the establishment of "Virginia." Shortly after, over 100 British men, women, and children boarded the ship Lyon, and ten weeks later, landed on the coast of North Carolina.
Roanoke Island was only meant to be a stopping point in the settlers' journey, as records show they intended to move 50 miles into the mainland, eventually making their home in Salmon Creek. But winter derailed their plans, forcing them to settle in Roanoke for longer than intended. The changing seasons, as well as a tenuous relationship with the local Algonquian tribe, the colony's governor John White to return to England to gather supplies. On August 25, 1587, the settlers asked, "...we all of one mind, and consent, have most earnestly entreated, and incessantly requested John White, Governor of the planters in Virginia, to pass into England, for the better and more assured help..." White was reluctant, but realized supplies would be beneficial, so on August 27, he set off for his home country.
His return trip was particularly ill-timed as it took place in the midst of the war between Spain and England. The threat of the fearsome Spanish Armada caused Elizabeth I to prohibit British ships from leaving the port, lest they be needed to face off against the Spaniards. In April 1588, despite the prohibition, White was able to arrange a relief mission. However, a battle with the French forced the ships to return to England.
White was unable to arrange another voyage until 1590, this time with four ships owned by privateers, who agreed to drop him off at the colony. On August 18, 1590, he landed in Roanoke and discovered the settlers had vanished without a trace, leaving behind only the word "Croatan" carved into a wooden post.
Croatan was the name of a nearby island that was home to a Native American tribe of the same name. Hypotheses about the fate of the settlers have ranged from kidnapping or possible assimilation into a tribe to a pandemic. But, nearly five centuries later, these theories are still unproven.
In recent decades, archaeological excavations have turned up few clues as to what took place in White's absence. Many researchers and archaeologists now believe that surviving settlers broke off into smaller groups and migrated to different areas. In 2020, the First Colony Foundation stated that "compelling evidence" had been found that a "satellite site" had been established along Salmon Creek for a period of time, as both excavations and ground-penetrating radar revealed ceramic artifacts that were later identified as being from the Elizabethan period.
The Foundation has also planned an excavation near Fort Raleigh National Historic Site in Manteo, North Carolina, in the hopes of finding the original settlement.
4.Ankhesenamun's (Nefertiti's daughter and King Tut's wife) tomb:
Despite her half-brother/husband, King Tut's final resting place being discovered in 1922, over a century later, the tomb of Ankhesenamun has yet to be uncovered.
Ankhesenamun, Nefertiti's daughter, was married to the "Boy King" when she was 13 years old. The couple had two daughters before Tut died around the age of 18 for causes that are still unknown. Ankhesenamun was featured prominently in the artwork within his tomb, including one scene that shows her assuming the role of priest during his coronation and again on the back of his golden throne.
After Tut's death, not much is known about her life, except for the fact that she initially refused to marry Ay, Tut's successor (and perhaps her grandfather). Instead, asking Suppiluliuma I, a Hittite king, to send one of his sons to marry her and therefore become pharaoh. This request confused the king, but he proceeded to send his son Zannanza, who was killed on the Egyptian border by General Horemheb (who later became pharaoh himself). A ring bearing the name of both Ankhesenamun and Ay seems to suggest that she eventually married him, but evidence supporting this theory has been inconclusive. Some also theorize that she may have been executed after communicating with the Hittites.
Despite her esteemed rank, Ankhesenamun's request to the Hittite king was the final time she was mentioned in the historical record, and her burial site has been lost to the sands of time. In 2016, archaeologists who scanned Tut's tomb believed they had found undiscovered chambers, which could possibly have led to Nefertiti or even Ankhesenamun's tombs. However, a later scan by National Geographic disproved this theory.
In 2017, Owen Jarus of LiveScience reported that archaeologists believed they had found Ankhesenamun's final resting place in the Valley of the Monkeys, which was adjacent to the Valley of the Kings. However, the dig's leader, Zahi Hawass, released a statement, claiming that they were not certain if a tomb existed at all and if it did, whether or not it belonged to Ankhesenamun.
As of 2025, nothing relating to Ankhesenamun's final resting place has been discovered.
5.The Ark of the Convenant:
Despite what one might believe after watching Raiders of the Lost Ark, the Ark of the Covenant has yet to be discovered. Throughout the centuries, individuals have searched for the Biblical artifact to no avail.
According to the Book of Exodus, during Moses' 40-day stay on Mount Sinai, God commanded him to have the Ark of the Covenant built and showed him a blueprint for a tabernacle for the Ark as well as furnishings it should contain. Constructed by Bezalel and Oholiab, the Ark itself was described as being made of acacia wood and overlaid with pure gold, with a crown of gold around it, and fitted with staves (vertical planks) overlaid with gold, so that it could be safely carried (in the books of Samuel and Chronicles, it is written that after a cart carrying the Ark tilted, a man named Uzzah reached out to steady it with his hand, which violated divine law, and was thereby killed by God for his error), and decorated with cherubims. The Ark was also designed to contain the original stone tablets on which the Ten Commandments were written.
The Ark was later lost to the Philistines (a group who had settled in Canaan) for seven months. However, after mishaps began plaguing the Philistines, they returned the Ark to the Israelites. Despite the significance of this artifact, it was last seen in Jerusalem within the Temple circa 586 BCE when the Babylonian Empire conquered the Israelites. To this day, historians are unsure if it was stolen, destroyed, or hidden.
Many believe the Ark made its way to Ethiopia. According to Ethiopian tradition, it was preserved in the Church of Mary of Zion in Aksum, an ancient holy city. Some even claim that Emperor Iyasu viewed and spoke to the artifact in 1691. Now, it supposedly resides in the Chapel of the Tablet, where it was moved during Haile Selassie's reign, and is guarded by a singular monk, who recites the Book of Psalms and burns incense before it. However, the church's authorities have never allowed the artifact to be studied for authenticity.
Another theory is that the Ark was hidden within a network of passages built underneath the First Temple in Jerusalem before the Babylonians destroyed it. However, this hypothesis cannot be tested because the site of the First Temple is now the Dome of the Rock shrine, which is sacred in Islam. Therefore, it cannot be excavated.
There are many, many theories about the Ark's current whereabouts. However, it seems unlikely we'll ever know what truly occurred, as archaeologist Fred Hiebert explained to National Geographic, "Even if such an object were discovered, how would one test its Biblical authenticity against that of other ancient artifacts? We are talking about things [at] the crossroads between myth and reality. I think it's great to have stories like [that of] the Ark of the Covenant. But I do not believe, as a field archaeologist, that we can use the scientific method to prove or disprove [them]."
6.Treasures of the Second Temple:
While we're on the topic of missing Biblical artifacts, it goes without saying that one of the biggest archaeological mysteries is the whereabouts of the treasures of the Second Temple.
After the Babylonians plundered the First Temple during their conquest of Jerusalem in 597 BCE, it was noted in the Book of Ezra that most of the stolen items were restored to the Israelites. However, over six centuries later, when the Roman emperor Titus laid siege to Jerusalem in 70 CE, the recovered treasures and many others sacred items (including the Golden Menorah, the Table of Showbread, and the golden altar of incense) that had been gathered over the centuries, vanished from the Second Temple.
When the Arch of Titus was constructed a few years later, the commemorative monument showed the Romans carrying their plundered treasures through the streets of their homeland. It was noted that some of these items were stored in the Roman Temple of Peace, where the Golden Menorah was displayed for centuries.
A little over three centuries later, the Romans were subjected to three days of looting and pillaging by the Visigoths, after which historian Procopius wrote that the invader's spoils contained, "the treasures of Solomon's Temple, a sight most worthy to be seen, articles adorned with emeralds, taken from Jerusalem by the Romans." The Visigoths resettled in the southern region of France, where some believe the pillaged treasures may still lie.
However, another theory states that the Visigoths were not so lucky as to keep their treasures. Many claim the items wound up in the possession of Byzantine Emperor Justinian, who believed them to be cursed and ordered their redistribution to churches in Jerusalem.
After the items were returned to their native land, some believe they were once again seized by either Persian or Muslim invaders and melted down. Others theorize they found their final home inside the mysterious Vatican vaults. However, in 2004, the Israel Antiquities Authority was granted permission to explore the vaults and found no sign of the items.
7.The Akkadian capital of Agade:
In 2334 BCE, Sargon the Great united all of Mesopotamia and developed the world's first multi-national political dynasty, the Akkadian Empire, which would serve as an example to all future Mesopotamian civilizations. At the height of its power, the Empire encompassed a large section of modern-day Iraq and Syria. Its people were known for pioneering innovations such as the world's first postal system and cuneiform writing. Akkadia was also recognized for Sargon's institution of Ishtar, the Semitic goddess of war, who served as the entire dynasty's deity, rather than just a single city.
This is what brings us to the lost city of Agade. Agade (also referred to as Akkade), Akkadia's capital, served as the Eulmash temple, which was devoted to Ishtar. However, when the Akkadian Empire fell around 2154 BCE, Agade had become largely abandoned. Later Mesopotamian rulers still revered the history of the empire, as Benjamin Foster, an Assyriologist, explained, "Their relics were admired, their inscriptions were studied, and their historical memory was kept alive for two thousand years."
Despite Agade's abandonment, the location of its ruins was still known in the 6th century BCE, as Babylonian king Nabonidus claimed to have excavated the site, writing, "I relaid the foundation, the altar, and dais, along with two ziggurats, and made firm its brickwork. I built them up to ground level so that the foundation of Eulmash shall never again be forgotten." Sadly, as is the case with many ancient sites, the location of the Eulmash temple and Agade itself had been mostly forgotten until the mid-1800s.
During the archaeology boom of the 19th and 20th centuries, Assyriologists once again took interest in ancient Mesopotamian culture and recognized Agade as a city of great cultural importance.
Historians today seem to agree that Agade was situated along the banks of the Tigris River, most likely between the modern cities of Baghdad and Samarra. However, due to the Tigris River changing course throughout the millennia, there is concern that Agade might have simply been washed away.
As Nele Ziegler, an Assyriologist for the French National Center for Scientific Research, explained, "We don't have many clues to where it is. There's no text that tells you, for instance, how much time it took to go from Sippar to Agade." She continued, "We'd really like to find it. There was a cultural revolution going on when the Akkadians came to power. It would be really interesting to see what they imagined as their ideal capital city." As of now, the city still remains lost.
8.The Heirloom Seal of the Realm:
In 221 BCE, the Heirloom Seal of the Realm (aka the Imperial Seal of China) was allegedly carved out of a sacred piece of jade, known as the Heshibi, under the orders of Qin Shi Huang, the first emperor of China, after he united the nation and destroyed the remaining Warring States.
When China's second emperor, known as Ying Huhai, died, the seal was gifted to the Han dynasty's new emperor, thereby becoming known as the "Han Heirloom Seal of the Realm." Years later, the sole emperor of the Xin dynasty forced the Han empress dowager to hand over the Seal. The Seal survived this and many more centuries of political turmoil; in all, it was passed through six dynasties before becoming "lost" during the Five Dynasties and Ten Kingdoms period, which lasted from 907 to 960 CE. While it is not known what specifically happened to the Seal, there are three prominent theories that allude to its disappearance, with one of the most prominent being that Yuan emperors acquired it.
However, that theory is slightly discredited after one learns that when Ming armies captured the Yuan capital in 1369, they gained ownership of only one out of the emperor's eleven seals. When Ming armies invaded again the following year, the Seal was still missing. Once the Ming dynasty began, the Seal was officially considered lost, and over six and a half centuries later, it still is.
Several ancient seals have been discovered in the Chinese countryside in recent decades, which have drawn many excited hypotheses that they could have been the long-lost Heirloom Seal. However, these theories have been disproven.
9.Cleopatra's tomb:
On August 10 (or possibly 12), 30 BCE, after Egyptian forces were crushed by the Roman army in the Battle of Actium, Cleopatra killed herself. Despite it being over two millennia since the queen was found lying, lifeless, on her golden couch, we still do not know where her final resting place is. According to ancient historians, Octavian, the Roman ruler, allowed Cleopatra and her husband, Mark Antony, who had killed himself nine days prior, to be buried together.
In his writings, Plutarch stated that Cleopatra's tomb was located near a Temple of Isis (the Egyptian goddess of healing and magic), as both he and fellow historian Cassius Dio noted that in her final days, she had frequently traveled from her palace to the tomb. Dio further supported the claim that she and Antony "were both embalmed in the same fashion and buried in the same tomb."
In 2004, Kathleen Martínez, a lawyer-turned-archaeologist, began searching for the tomb. After studying Ancient Roman texts, Martínez investigated 21 temple sites she believed could house Cleopatra's remains, leading her to primarily focus on Taposiris Magna, a ruined temple which lies 25 miles west of Alexandria.
She told National Geographic, "What brought me to the conclusion that Taposiris Magna was a possible place for Cleopatra's hidden tomb was the idea that her death was a ritual act of deep religious significance carried out in a very strict, spiritualized ceremony. Cleopatra…wanted to be buried with [Antony] because she wanted to reenact the legend of Isis and Osiris. The true meaning of the cult of Osiris is that it grants immortality. After their deaths, the gods would allow Cleopatra to live with Antony in another form of existence, so they would have eternal life together."
In December 2024, her team discovered a small marble bust that the Egyptian Ministry of Tourism and Antiquities claimed Martinez told them might bear the resemblance of Cleopatra, however, in the press release, the Ministry noted that other archaeologists disagreed with her theory, claiming the "facial features differ from known depictions of Cleopatra VII. It is more likely the statue represents another royal woman or princess."
Despite some impressive findings, Martinez and her team have yet to locate Cleopatra's final resting place. Zahi Hawass, an early supporter of Martinez's work and the former secretary-general of the Supreme Council of Antiquities, told Live Science, "There is no evidence at all that Cleopatra's tomb could be in [Taposiris Magna]. I believe now that Cleopatra was buried in her tomb that she built next to her palace and it is under the water. Her tomb will never be found."
Did any of these "lost" historical sites surprise you? Can you think of any other important historical locations that haven't been discovered? Let us know in the comments!

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A private detectorist surveying a farm in northern Jutland found a concentration of jewelry—gold rings, dress pins and cloak clasps—so substantial that Trier mounted a rescue dig to stabilize whatever archaeological context had managed to escape the plow. Over the next two years Trier and a team of professional archaeologists uncovered a vast burial complex with hundreds of graves, many including human remains, their heads all oriented west toward the North Sea. Farming and erosion had eaten away at the topsoil for so long that only a few centimeters of depth covered many of the graves. 'One or two more seasons of plowing and they would have been gone,' Trier says. Just a kilometer away from the Vaarst complex is a modern town called Gudum. Historians had puzzled over the origin of the town's name, which translates to 'home of the gods.' Now, thanks to the detectorists' find, researchers believe it might have been the site of a major religious center. It's a big ask to expect the finder of a pristine ancient treasure to turn it over to a government bureaucracy. Detectorists find ways to keep their favorite artifacts close to their hearts. Detectorists hand over their artifacts to Denmark's 28 local archaeology museums—an astonishing number for a country one-third the size of New York State. It's up to local archaeologists such as Trier to designate sites of interest before they're destroyed by farming or construction and to identify and record the finds before they're passed on to the central Danefæ department at the National Museum. Trier says he has about 300 detectorists who regularly turn in finds to him. 'They can often tell even from a teeny sound the detector makes what kind of an object and how deep it is,' he notes. Some private detectorists have résumés that rival those of professional archaeologists. On an uncharacteristically sunny day in March, husband-and-wife duo Kristen Nedergaard Dreiøe and Marie Aagaard Larsen picked me up at a train station in southern Denmark, in an area north of the border with Germany. 'You know, people used to call this place the 'rotten banana' of Denmark,' Aagaard told me. But not anymore. The detectorist power couple's finds have revealed that the area where Aagaard grew up was an important hub of wealth and power 1,000 years ago. In 2016 Aagaard, Dreiøe and their friend the late Poul Nørgaard Pedersen discovered nearly 1.5 kilograms of Viking Age gold artifacts near the modern town of Fæsted, including armbands that archaeologists have interpreted as oath bands: twisted rings that would have been given by a chieftain or lord to his lieutenants to wear as a sign of their fealty. It's the largest hoard of Viking gold ever discovered in Denmark. But Aagaard and Dreiøe haven't let the gold go to their heads in the decade since. Quite the opposite: they show an unusual willingness to investigate every signal on their detector, even for iron. Iron is a perennial pest for detectorists. It elicits a loud, petulant scream from the detector and is almost always farm trash. Once detectorists become experienced enough to recognize this sound, most won't lift a shovel for it. Aagaard and Dreiøe's dogged digging, however, led them to discover a cache of more than 200 iron weapons—spears, lances, daggers and swords—in 2018. Subsequent excavations by the local archaeologist, Lars Grundvad, uncovered a series of temples used by what he calls a 'cult of destruction' starting around C.E. 0. They found evidence of at least 15 incarnations of the temple, each a few meters apart from the rest, spanning an estimated 550 years, Grundvad said. Many of the weapons seem to have been placed in support poles—whether as sacrificial offerings in the inauguration of a new temple or as a way of symbolically 'killing' the old one remains unclear. Fifteen temples 'felt very Indiana Jones,' Aagaard says. Looking back, Aagaard and Dreiøe laugh when they remember they considered taking up hunting or sailing as their joint hobby instead. The dig site I visited with Aagard, Dreiøe and Grundvad in March is in a field where grain is typically grown, just a stone's throw from a highway. On the horizon we could make out a suburban neighborhood, windmills—and a dolmen, a burial mound with large stones perched atop it, probably about 5,000 years old. The dolmen was already ancient by the time of the Vikings, Grundvad mused. The museum had rented a lime-green excavator for the occasion. A young tradesperson operating the digger painstakingly scraped layers of just a few centimeters of soil at a time from the surface of the ground over an area about the size of two basketball courts. Four metal detectorists, including Aagaard and Dreiøe, had taken the day off from work to participate. Supervised by a pair of local archaeologists, they followed behind the excavator as it crept through the plow layer toward what we hoped would be an undisturbed archaeological context. Just 20 minutes in, Dreiøe let out a triumphant whoop. The archaeologists and detectorists all gathered to see a Roman silver coin called a denarius cradled in his palm. 'Today is like my birthday, New Year's and Christmas in one,' Aagaard said. As the day wore on, about 10 more coins in bronze and silver, carefully labeled in individual baggies, accumulated in Grundvad's bucket of finds. But the archaeologist was more interested in a small, curved piece of bronze that Aagaard found: a fragment of a goblet or a pot the coins might have been buried in. The hope is that deep under the plow layer, there might be evidence of a settlement. Grundvad treats Dreiøe and Aagaard—who are, by trade, a sales manager and a psychologist, respectively—as colleagues. 'At first we wondered if they'd roll their eyes at us because archaeology is their job and our weekend hobby,' Aagaard says. 'But not Lars. He's one of the youngest and hippest local archaeologists.' Nearly every weekend during the detecting season, Aagaard and Dreiøe take their 'time machines' out in the field. They send snapshots of their discoveries to Grundvad for immediate identification. 'Not to sound arrogant about it, but we've gotten used to them bringing in extremely nice finds,' Grundvad said. In many ways, he credits Dreiøe, Aagaard and Nørgaard with putting his little museum on the map. It's a very different mentality than his colleagues in Sweden have, according to Grundvad. 'The Swedish authorities think that metal detectorists will destroy finds, take them out of their context. We think the finds are being saved.' The oldest wing of the National Museum, in downtown Copenhagen, is home to Denmark's treasure bureaucrats. It's up to the curators of the Danefæ department to identify the thousands of objects streaming in from the fields every year and decide which are worthy of joining the museum's research collection—and which will earn their finders a monetary reward. Even though detectorists can now upload photographs and GPS coordinates of their finds to a dedicated app, the curators' identification process remains much as it was 40 years ago. The best resources are thick reference books, their margins filled with hand-drawn diagrams and annotations from curators stretching back to the 1940s. With the breadth of objects that come across their desks, from flint-knapped stone tools and Bronze Age weapons to Viking jewelry, curators need an encyclopedic knowledge of Danish prehistory just to have a chance of knowing which book to reach for. Kirstine Pommergaard knows what style of brooch was popular in C.E. 300. She can tell whether a coin is a Roman solidus or a dirham of the ancient Islamic caliphates at a glance. 'You have to love items and the stories they can tell to be able to do what we do,' she says. Pommergaard is a curator of prehistoric archaeology and one of just three archaeologists in the country dedicated to identifying Danefæ full-time. As of 2025, there's a daunting backlog of more than 50,000 objects in a secret 'secure facility' awaiting evaluation. '[Each one is an] important piece of the puzzle, even if it's not made of gold or if we have 1,000 of them already,' she says. But what Pommergaard cherishes most are the items whose very existence reveals unforeseen connections. All the curators were dazzled when a detectorist turned in a solid gold ring set with a blood-red garnet. But Pommergaard, a self-professed craftsmanship nerd, became fixated on something many might have overlooked in the quest to figure out the origin of the ornament: the underside of the ring's setting. Four delicate curlicues that the goldsmith used to attach the shank to the head were a smoking gun for Pommergaard. This jewelry-making technique was exclusive to Frankish craftsmen living under the Merovingian dynasty, a royal dynasty that used marriage diplomacy to consolidate power across central Europe after the fall of the Roman Empire. Thumb rings with a similar construction have been found in the graves of high-status Merovingian women on the level of empresses and queens, Pommergaard says. Could the ring have been a spoil of war? The stone says otherwise. Although the Merovingian queens wore signet rings, red stones were a symbol of power among the Nordics. 'There must have been someone in Emmerlev who was important enough to marry one of their daughters off to,' Pommergaard says, referring to the hamlet nearest to where the ring was found. Before the discovery of the ring, Emmerlev was known only as the site of a cattle trade that operated in the 1500s. Pommergaard had dreamed of working with ancient items since she was seven years old, when she found half of a stone ax with her grandfather on the Danish island of Fyn. But what she probably didn't foresee—and what seems to be her least favorite part of the job—is being asked to put a price on the priceless. It falls to the Danefæ team to determine the finder's reward for each item chosen for the museum's collection. Most of the payouts are quite modest and far below what the objects might fetch on the black market—250 or 350 kroner (around $40 or $50) would be a typical finder's fee for a coin from the 12th or 13th century. But the blockbuster treasures can command eye-watering sums. Aagaard, Dreiøe and Nørgaard received just over a million kroner for the oath ring treasure, the equivalent of about $150,000. Ginnerup—the discoverer of the golden bracteate with Odin's name—declined to share how much he received for his hoard. 'The National Museum emphasizes not to talk about the money,' he says. Pommergaard says she isn't allowed to discuss how they decide the payouts, only that they consider an artifact's historical value and condition and the care the finder took in collecting it. Altogether, Danish detectorists received the equivalent of $1.3 million in 2023, up from just $130,000 in 2012. Technically the sky's the limit—the law doesn't stipulate a cap on Danefæ payouts. But the same can't be said of the budget for archaeologists to process the finds. Currently the average wait for an artifact to be processed by the Danefæ team is 'at least 2.5 years' once the object reaches their doors, according to Pommergaard, but that duration doesn't include the time the objects spend being evaluated at local museums, which don't receive dedicated funding for Danefæ. As local museums struggle to process the finds their detectorists turn in, they risk missing the opportunity to identify sites such as the Vaarst complex before they're lost to construction or the plow, Trier says. The long processing time also means some prolific detectorists have tens of thousands of kroner in rewards tied up in the system, sometimes for up to a decade. But archaeologists and hobbyists agree that detectorists aren't in it for the money. 'Hour for hour, we'd be better off picking up cans off the side of the road and turning them in for the recycling fee,' says Troels Taylor, a longtime detectorist based in Zealand. Nevertheless, 'we are grateful for our system where we get a little reward for the huge work and effort we do,' Taylor adds. Detectorists do want to know their finds are being examined and used for research, however. If not, they'd be happy to display them in their homes. It's a big ask to expect the finder of a pristine ancient treasure to turn it over to a government bureaucracy. Detectorists find ways to keep their favorite artifacts close to their hearts. Taylor, like many detectorists, has several tattooed on his body, including one image from a strap end he found of two stylized beasts that twist on his forearm. Other detectorists, such as the finder of the royal Emmerlev ring, hire metalsmiths and jewelers to make re-creations of their discoveries. The Danefæ program provides a tremendous return on investment from the perspective of the Danish government, Trier says. Private detectorists spend thousands of hours in the fields, and taxpayers pay them only when something extraordinary is uncovered. But simmering frustration with wait times risks upending the program. 'Our system is working really well, but it's only working because the detectorists feel heard—they feel that they are contributing and that we're actually taking them seriously,' Trier says. If processing times get any longer, however, he worries the program will stretch the detectorists' goodwill. 'The trust system only works as long as we archaeologists supply our part of the deal.' But many detectorists say that even if wait times ballooned, they doubt they'd ever be able to give up their hobby. 'As long as I can walk and dig holes,' Ginnerup says, 'I will continue with my metal detector.'

National Geographic

6 days ago

• National Geographic

Use this ancient technique to remember (almost) anything

In Orlando, Florida, a dozen seniors gather in a YMCA twice a week. Some push walkers, others roll in on wheelchairs. After some light exercise and corny jokes, they get down to the real workout—flexing their memory muscles. Most are battling early-stage dementia, hoping to hold onto their memories a little longer. They're learning an ancient technique called the method of loci, which transforms any familiar space into a storage system for new information. Want to remember your grocery list? Link milk to your sister's senior photo in the living room—visually, and in a way that feels almost absurd. Maybe imagine it pouring out of her nose? Link apples to the window—a volley of Golden Delicious smashing through the pane. The Roman orator Cicero used the same method to memorize speeches two millennia ago. Today's competitive 'memory athletes' use it to cram thousands of data points into their brains. And now the ancient technique is helping people in surprising new ways —slowing cognitive decline, treating depression and PTSD, even aiding recovery from traumatic brain injury. As researchers are only just now discovering, this tool works in startlingly complementary ways with how our brains naturally function. The palace of the mind At the USA Memory Championship, seemingly ordinary people show off extraordinary recall. Competitors memorize hundreds of random words, dozens of strangers' life histories, and the order of shuffled card decks—all at lightning speed. These are the kinds of folks who might rattle off a thousand digits of pi without breaking a sweat. They all use variations on the method of loci, also known as the 'memory palace' or 'Roman room' method. The basics are straightforward: Make a mental map of a familiar place, then create associations between items and specific locations along a route. But is it easy? Not necessarily. The trick is using your imagination to make those mental connections memorable—the weirder, more vivid, and more outrageous, the better. Legend credits the method's invention to the ancient Greek poet Simonides of Ceos, who escaped a collapsing building in the fifth century B.C.E. As victims were pulled from rubble, Simonides identified them by remembering where each had sat around a banquet table. But indigenous cultures worldwide tapped into similar techniques long before. Native American pilgrimage trails, Australian Aboriginal songlines, and Pacific Islanders' ceremonial roads all follow a similar pattern: Elders would sing, dance, or tell stories at specific locations, making information stick by pairing information with location and context. 'It's shocking to me that this is so understudied when this was the dominant form of information storage for literally all of civilization, until the printing press,' says MIT neuroscientist Robert Ajemian, who has studied how the brain uses the method of loci. The event finalists are given instructions during the 2023 USA Memory Championship at Full Sail University, Winter Park, Florida. Photograph by Phanindra Pavuluri Why the memory palace works Neuroscience is catching up to what ancient cultures seemed to know instinctively. The method of loci taps our natural strengths in spatial navigation and visual memory—abilities that evolution has honed over thousands of generations. While almost no one is naturally great at remembering abstract information, like numbers or words, the human brain is built to remember what we've seen and where we've been. Recent brain-imaging studies show that using the method of loci creates more robust networks by linking multiple parts of the brain involved in memory: the prefrontal cortex, hippocampus, and visual cortex. Memory palace practitioners are literally rewiring their brains to be more efficient at memory. And after mastering the technique, they can develop elaborate systems of personalized imagery to represent, say, numbers, individual playing cards, or other hard-to-remember info. Despite their effectiveness, variations on the method of loci are neither widely taught nor widely researched, Ajemian says—much to his frustration. We've been too quick to dismiss it as a neat trick, he argues, instead of regarding it as a valuable learning tool that's sustained human knowledge for millennia. Perhaps nowhere is its potential more poignant than in the fight against dementia. New hope for aging minds For Michael Dottino, memory is the family business. His father founded the USA Memory Championship, and Michael trained businesspeople and students in memory techniques. Then the local Jewish Community Center asked him to try something new: develop a class for seniors with early-stage dementia. The Memory Institute program he created meets twice a week at the Dr. P. Phillips YMCA in Orlando. The four-hour sessions combine memory training with physical activity, social interaction, and cognitive exercises like using the method of loci. The goal, Dottino says, is to slow participants' rates of decline. Three years in, he finds the program's results encouraging. Some of the earliest participants are still showing up twice a week, keeping up the regimen. Dottino calls out one of them, Karen Vourvopoulos, who has retained all of her cognitive function. 'The class has given my mother a new lease on life,' says Matina Vourvopoulos, Karen's daughter. 'She's more energized, inspired, creative, and enthusiastic about life. I wish there was a Memory Institute for every senior in every community.' Clinical neuropsychologist Erica Weber is putting similar approaches through rigorous clinical trials. Memory programs are few and far between, she says, and patients often pay out of pocket. But if such strategies can be proven genuinely effective, insurance companies might start covering them. One current challenge, Weber says, is that the main sources of funding for rehabilitation research—the U.S. Department of Defense and the National Institute on Disability, Independent Living and Rehabilitation Research—are facing large cuts (and, in the latter case, outright elimination). But so far, the research looks promising. One massive study, funded by the National Institutes of Health, showed that cognitive training can help healthy older adults maintain and improve their mental skills. Though there's no need to wait until retirement age to put memory strategies like the method of loci to use. 'Try to practice using the strategies before you need to rely on them,' Weber advises. Think of it as a cognitive gym membership—better to start lifting mental weights before the muscle gets weak. Applications beyond aging Which is to say, seniors aren't the only ones who can benefit. Weber adapts the method of loci to help people with traumatic brain injuries—suffered in car accidents or falls, for example—to recover cognitive function. What she calls the modified Story Memory Technique breaks down memory palaces into simpler components, like transforming verbal information into mental imagery. The range of patients she works with keep expanding, including those suffering from multiple sclerosis, HIV-related cognitive impairment, and spinal cord injuries that impact brain function. Perhaps most intriguingly, mental health experts are exploring the memory palace as a therapy tool. People with depression or PTSD might create palaces filled with positive memories, mental refuges to revisit during tough times. The concept makes intuitive sense: if you can train your brain to efficiently store and retrieve any information using spatial memory, why not train it to access calm, positive states when you need them most? In our smartphone age, when we've outsourced so much memorization to Google and GPS, ancient mnemonics are reminders of what our remarkable brains can do. As MIT neuroscientist Ajemian puts it, engaging these techniques is 'fundamental cognitive exercise, in the same way that aerobics is fundamental physical exercise.' Our ancestors carried entire libraries in their heads. With a little practice, we can at least make sure to pick up the milk. This article is part of Your Memory, Rewired, a National Geographic exploration into the fuzzy, fascinating frontiers of memory science—including advice on how to make your own memory more powerful. Learn more.