If you want to find buried treasure, usually X marks the spot.
But some rare riches don鈥檛 appear on any ancient maps and their location is completely unknown.
大象传媒 Bitesize takes a look at famous missing treasure and items around the world.
Jules Rimet Trophy
You鈥檝e probably heard of Jules Rimet every time England are playing in a major football tournament. The song Three Lions refers to the Jules Rimet Trophy, given to England for winning the 1966 World Cup. It was named after the Fifa President at the time of the first tournament in 1930.
But the trophy has had quite a chequered past. Shortly before the 1966 World Cup, the trophy was stolen from a public exhibition at Westminster Central Hall. It was eventually found in south-east London by David Corbett and his dog Pickles.
But that wasn鈥檛 the end of the trophy鈥檚 drama. After winning the tournament for a third time in 1970, the trophy was permanently awarded to Brazil.
In 1983, it was taken from the Brazilian Football Confederation鈥檚 headquarters by a group of men. It was originally claimed that the trophy was melted down into gold bars 鈥 but this has been disputed, as it was not solid gold, but gold-plated silver.
Rather than still gleaming, Jules Rimet is still missing and the whereabouts of this piece of football history may never be discovered.
Irish Crown Jewels
Thought to be worth several million pounds today, the Irish Crown Jewels were stolen more than a hundred years ago 鈥 and have never been found.
The collection consisted of a star, decorated with diamonds, an emerald trefoil and a ruby cross, a diamond badge and five jewel-encrusted golden collars. They were made up of almost 400 jewels, most of which were taken from Britain鈥檚 Queen Charlotte鈥檚 collection.
The jewels were not worn by the monarchy themselves. They were linked to the Order of St Patrick and were worn by the Grand Master of the Order 鈥 the Viceroy who represented British power in Ireland.
At the turn of the 20th Century, the jewels were housed in the Bedford Tower, in the upper courtyard of Dublin Castle. They were kept in a safe room in the tower, but on the 6 July 1907, a cleaner found the room鈥檚 outer door was wide open.
The inner door leading directly to the jewels was closed, but with a key in the lock. Some time later, when another item was to be placed in the safe room, they discovered the collection of jewellery was missing.
Many of the team responsible for guarding the jewels were accused of stealing them, but police were unable to solve the mystery, despite offering a substantial reward. To this day, they have never been recovered.
Honjo Masamune
It鈥檚 around 700 years old and was named a Japanese National Treasure in 1939 鈥 but no-one knows where the legendary Honjo Masamune sword is today.
Master Japanese sword maker Goro Hyuno Masamune learned the craft of swordmaking in the late 13th-Century, producing weapons unrivalled by any other.
In order to improve the quality of the swords he produced, Masamune blended soft and hard steel together which produced a unique wavy pattern on the blades. His work was so acclaimed, he was named chief swordsmith by Emperor Fushimi.
His most well-known piece became known as Honjo Masamune, named after the first prominent general to use it, Honjo Shigenaga.
In the aftermath of World War Two, the US demanded that all Japanese citizens should hand in their weapons, including swords. The ruling Tokugawa family, who were in possession of the sword, wanted to set an example so gave the Honjo Masamune to the US Army.
But what happened next isn't fully known. It's thought that the Honjo Masamune may have been sent back to the United States, melted down or kept by a soldier - but no-one can say for sure. There is hope it will be discovered one day - another Masamune sword was found in 2014 after being missing for 150 years and was then donated for display in the Kyoto National Museum.
Ark of the Covenant
While the world鈥檚 most famous fictional archaeologist may have discovered the Ark of the Covenant on the big screen, no-one has matched Indiana Jones鈥檚 efforts in real life.
The Ark is a gold-plated wooden chest, built by the Israelites and believed to have housed the stone tablets which were engraved with the Ten Commandments.
It was thought the Ark was so sacred, touching it would result in instant death. According to the Hebrew Bible, the Levites were instructed to carry it by using two wooden poles. The Ark was said to have other powers 鈥 with Bible verses stating that it was able to part waters to cross the Jordan River and was also used in battle to defeat enemies.
The Hebrew Bible says the ark was taken to Jerusalem and later placed in the city's temple. It's believed it was last seen around 587BC at the time of the Babylonian siege of the city in which the temple was destroyed - the whereabouts of the Ark were unknown.
According to Ethiopian Christian tradition, the Ark rests in the town of Aksum in the country鈥檚 northern highlands but no-one other than its guardian may see it. There have also been other claims it has been seen in Egypt, Ireland, Italy, France and the United States, among others 鈥 but none of these reports have ever been verified.
This article was published in April 2022
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