The Olympic-class ocean liners were a trio of ocean liners built by the Harland & Wolff shipyard for the White Star Line during the early 20th century. They were Olympic, Titanic, and Britannic. Two were lost early in their careers: Titanic sank in 1912, after hitting an iceberg in the North Atlantic, and Britannic in 1916, after hitting a mine or torpedo laid by the German minelayer submarine U79 in a barrier off Kea during World War I.