The Battle of Iwo Jima, which began on 19 February 1945, was arguably the most famous Marine engagement of the war. The Japanese had learned from their defeats in the Marianas Campaign and prepared many fortified positions on the island including pillboxes and network of tunnels. The Japanese put up fierce resistance, but American forces reached the summit of Mount Suribachi on 23 February. The mission was accomplished with high losses of 26,000 American casualties and 22,000 Japanese.