Manus Naval Base was a number of bases built after the World War II Battle of Manus by United States Navy on the Manus Island and a smaller island just east, Los Negros Island in the Admiralty Islands chain. The major naval base construction started with the Los Negros landings on February 28, 1944. The Navy repaired and did the expansion of the airfields on the Admiralty Islands. United States Navy Seabee built or repaired the facilities on the islands. The large Manus Naval Base, also called the Admiralty Island base, supported United States Seventh Fleet, Southwest Pacific command, and part of the Pacific Fleet. The base was abandoned by the US Navy after the war.