The Titanic sank to a depth of approximately 13,000 feet in the north Atlantic on April 15, 1912. The depth was not discovered until a joint French-U.S. expedition found the ship in 1985.
American Dr. Robert Ballard made it his mission to find the remains of the Titanic in the 1980s so that historians could understand more about what happened that night. Using funding from the U.S. Navy, Ballard and his French colleagues found the wreck on Sept. 1, 1985, on the second of two expeditions. Because the ship lay so far under the surface of the ocean, manned and unmanned submersibles were needed for the exploration.