USS Indianapolis (CL/CA-35) was a Portland-class heavy cruiser of the United States Navy. She was named for the city of Indianapolis, Indiana. She was the flagship of Admiral Raymond Spruance while he commanded the Fifth Fleet in battles across the Central Pacific. Her sinking led to the greatest single loss of life at sea in the history of the U.S. Navy. On 30 July 1945, after delivering parts for the first atomic bomb to the United States air base at Tinian, the ship was torpedoed by the Imperial Japanese Navy submarine I-58, sinking in 12 minutes. Of 1,196 crewmen aboard, approximately 300 went down with the ship.