The Greatest Underwater Treasures Ever Found

With nearly three-quarters of the planet covered in water, what lies beneath the surface hides more than undiscovered marine species — it also holds treasures lost at sea.

Sea crossings were recorded as early as 60,000 to 70,000 years ago. As people explored and met other cultures, trading began, using ships to transport goods not found in their own lands. Ships were also used to move cargo, including precious minerals mined from the Earth.

Yet, all of marine history has not been smooth sailing. What happened to ships that never arrived with their precious cargos now inspires the dreams of treasure hunters. Although there are many known — and unknown — treasures still lost, we examine some of the greatest underwater treasures ever found.

The Spanish Nuestra Senora de las Mercedes was a 36-gun frigate that met its demise in 1804. The ship was transporting silver, gold and spices from Uruguay to Spain. When the British Navy demanded to inspect the ship just off the coast of Portugal, the Spanish refused.

The ship lost a battle against four British Royal Navy ships, and it sank to the bottom of the Atlantic with more than 200 people on board. It took only one bullet to cause her sinking, with survivors rescued only to become prisoners.

Odyssey Marine Exploration first discovered the ship in 2007, mistaking it for a British ship thought to have sunk in 1641. However, the finders were not the keepers of the massive $500 million worth of treasure found in the recovery of Las Mercedes. 

The Spanish government sued the exploration team in 2012, retrieving all the booty that was rightfully theirs — 17 tons worth of silver and hundreds of gold coins.

Ever since, an extensive touring exhibit of the treasure and the shipwreck’s history has traveled to several Spanish public museums, including the Spanish Naval Museum and the National Archaeological Museum of Spain.

A British cargo ship, the SS Gairsoppa was returning from India carrying a heavy load of silver ingots. When a heavy storm appeared, the captain changed the ship’s course to head toward Ireland instead of England. Unfortunately, it was 1941 during the height of World War II.

A German plane spotted the ship and sent its location to a German U-boat. Shooting a torpedo at the SS Gairsoppa, the ship went under, claiming the lives of its 85 passengers.

Treasure seekers knowing there was silver to be found long sought the ship after the war ended. It was Odyssey Marine’s team that discovered it in 2011 — more than 14,000 feet below the surface. Since the discovery, more than 110 tons of silver ingots have been recovered from SS Gairsoppa.

After subtracting operating costs, the Odyssey team got to keep 80 percent of the find, giving 20 percent to Her Majesty’s Treasury. Letters, bottles, teapots and silk sheets were also recovered and presented in the “Voices From the Deep” exhibition at London’s Postal Museum.