1. Ark of the Covenant

According to the Hebrew Bible, Moses had the ornate, gold-plated wooden chest known as the Ark of the Covenant built according to God’s own design. Its purpose was to guard sacred relics, including two stone tablets containing the Ten Commandments. The Israelites carried the Ark throughout their 40 years spent wandering in the wilderness and later housed it in King Solomon’s temple in Jerusalem.

In 607 B.C., the Babylonians besieged the Israelite capital, slaughtering more than a million people and driving the survivors into exile. When the Israelites returned, the Ark had disappeared, along with many other priceless treasures. It’s unknown whether the holy chest was hidden somewhere before the siege as protection, or destroyed by the Babylonian invaders. Whatever the case, archaeologists and treasure hunters have been searching for it for more than a century, with little success.

2. Montezuma’s Treasure

When Hernán Cortés arrived in the Aztec capital of Tenochtitlan in 1519, Emperor Montezuma II greeted him and his men with great ceremony. The Aztecs even offered Cortés gold and silver in the hopes that these white-skinned “gods” would leave Tenochtitlan in peace. Greedy for more, the Spaniards put Montezuma under house arrest instead, and with the help of local allies set about ransacking the city and terrorizing its inhabitants.

After a brutal massacre during a religious festival, the Aztecs rose in rebellion, and Montezuma was killed in the confusion. Spanish forces fled Tenochtitlan under full attack, and were forced to dump all their looted riches in the waters of Lake Texcoco in their mad rush to escape. Though Cortés returned with a rebuilt army the next year and conquered the Aztecs for good, the so-called “Montezuma’s Treasure” would remain lost. According to the most popular theory, the riches still rest on the bottom of Lake Texcoco, though many have searched for it there without success. But as one legend—handed down by some Aztec descendants—has it, more than 2,000 men retrieved the treasures and marched them (with Montezuma’s exhumed corpse) north, perhaps all the way to southern Utah.

Montezuma II (Credit: Hulton Archive/Getty Images)
Hulton Archive / Getty Images
Montezuma II.

3. Blackbeard’s Treasure

History’s most famous pirate (real name: Edward Teach) is thought to have served as a British privateer during the War of Spanish Succession in the early 18th century before embarking on his brief but notorious career in piracy. From 1716 to 1718, Blackbeard and his 40-gun flagship, Queen Anne’s Revenge, prowled the West Indies and the Atlantic coast of North America, preying on ships heading back to Spain laden with gold, silver and other treasures from Mexico and South America. In late 1718, a British naval force led by Lieutenant Robert Maynard succeeded in killing Blackbeard after a hard-fought battle; Maynard had the infamous pirate decapitated and hung his head from the bowsprit of his ship. Before his death, Blackbeard claimed to have hidden his massive treasure, but he never told anyone its location. Treasure hunters have been searching for it ever since, seeking clues everywhere from Virginia’s Chesapeake Bay to the Caribbean and the Cayman Islands.

4. Treasure of Lima

In 1820, as the forces of the revolutionary leader José de San Martín advanced on Lima, Peru, Spanish authorities hurried to save the riches they had amassed since their conquest of the Inca Empire in the 16th century. They entrusted the British sea captain William Thompson to hide the treasure aboard his ship, the Mary Dear, and sail around until it was safe to return to Lima. Instead, Thompson and his crew killed the Spanish viceroy’s guards and took off with the loot. When a Spanish ship captured the Mary Dear, the entire crew was executed except for Thompson and his first mate, who promised to reveal where they had buried the treasure. But when they reached Cocos Island, near present-day Costa Rica, Thompson and his mate escaped into the jungle and were never heard from again. Since then, more than 300 expeditions have tried—and failed—to find the Treasure of Lima. The lost haul, which reportedly included a life-size solid-gold image of the Virgin Mary encrusted in gems, is thought to be worth around $200 million today.

5. Mosby’s Treasure

In early March 1863, the Confederate ranger Colonel John Singleton Mosby and his band of guerrilla raiders surprised more than 40 Union troops at the Fairfax Courthouse and overcame them without firing a shot. From the lodgings of Union General Edwin Stoughton, Mosby reportedly took a burlap sack stuffed with more than $350,000 worth in gold, silver, jewelry, candlesticks and other family heirlooms, all of them taken from the homes of wealthy Virginia planters. While Mosby was transporting Stoughton and the other prisoners back to the Confederate line, his scouts warned him of a large detachment of Union soldiers nearby. In case of a battle, Mosby told his men to bury the sack of treasure between two large pine trees, which he marked with his knife. Mosby’s raiders avoided the clash and got back behind Confederate lines, but when he sent back seven of his men to retrieve the riches, they were caught and hanged as accused guerrillas. Mosby never returned to get the treasure and never told anyone else its exact location—as far as we know, it remains buried in the woods of Fairfax County, Virginia, today.

6. Nazi Gold in Austria’s Lake Toplitz

A scuba diver passes forged Nazi banknotes found in Lake Toplitz. They notes were forged during WWII in an attempt to destabilize the British economy, but were dumped in the lake at the end of the war. (Credit: Keystone/Getty Images)
Keystone / Getty Images
A scuba diver passes forged Nazi banknotes found in Lake Toplitz.

During the final months of World War II, as Germany found itself on the brink of defeat, the Nazi regime sought to hide the valuable treasures it had spent the past six years looting from museums and doomed Jewish families all over Europe. Even today, rumors continue to circulate of a Nazi “ghost train” carrying up to 300 tons of gold and other riches through a secret network of tunnels in Poland. In Lake Toplitz, located in a thick Alpine forest in Austria, Nazi officers are believed to have sunk billions of dollars worth of Reichsbank gold—none of which has been recovered so far. In 1959, divers retrieved containers filled with millions of dollars worth of fake currency from Allied nations, part of a Nazi plan to destroy their enemies’ economies through inflation. To date, at least seven people have drowned in the lake’s freezing waters looking for the lost Nazi gold.

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