A team of researchers has found the world's oldest intact shipwreck. The Black Sea Maritime Archaeology project recently found the wreck off the coast of Bulgaria. It's believed to be from a Greek merchant ship. Carbon dating has shown it to be more than 2,400 years old! The ruins were discovered more than a mile underwater, in oxygen-free conditions that helped preserve the ship's parts. It's just one of several ancient vessels the Black Sea Archaeology project has found over the past three years.