Fleet Activities Yokosuka (Yokosuka Naval Base)

United States Fleet Activities Yokosuka (CFAY) is a United States Navy shore installation in Yokosuka, Kanagawa Prefecture, Japan. It lies at the entrance of Tokyo Bay on the Miura Peninsula in central Honshu, some 65 km south of Tokyo. Its mission is to operate and maintain base facilities providing logistic, administrative, service and recreational support to U.S. Naval Forces Japan, the Seventh Fleet and other operating forces assigned to the Western Pacific. The installation covers about 2.3 km2 and is the largest U.S. naval base in the western Pacific.

Roughly 55 tenant commands are resident. Yokosuka is the homeport of the principal afloat elements of the Seventh Fleet, including the fleet flagship USS Blue Ridge (LCC-19), berthed there since 1979, and the Navy's only permanently forward-deployed aircraft carrier, which serves as flagship of Carrier Strike Group Five. Destroyer Squadron 15 homeports Arleigh Burke-class guided-missile destroyers at the base. Forward deployment of a complete carrier task group began on 5 October 1973, when USS Midway arrived with Carrier Air Wing Five under an accord concluded between the United States and Japan on 31 August 1972; Independence relieved Midway in August 1991 and Kitty Hawk relieved Independence in August 1998. Following a 2005 announcement, the conventionally powered carrier was replaced by the nuclear-powered Nimitz-class USS George Washington (CVN-73), which arrived on 25 September 2008. Yokosuka Submarine Base was established in September 1945.

Ship maintenance is handled by the Ship Repair Facility, formed as the Ship Repair Department in April 1947, raised to component command in April 1951 and subsequently redesignated; it is the principal U.S. naval repair yard in the Far East and supported Seventh Fleet ships through the Korean and Vietnam Wars. Supply support is provided by the Naval Supply Depot, established August 1952 from the Fleet Activities supply department. Other tenants include U.S. Naval Hospital Yokosuka, commissioned in 1950, communications facilities commissioned in January 1951 and redesignated Naval Communications Station, Japan in 1960, and Marine Barracks, U.S. Fleet Activities, Yokosuka, redesignated in May 1946. Housing is dispersed, including the Ikego Housing Area. The adjacent JMSDF Yokosuka Naval Base occupies parts of the former Japanese naval district.

The site was developed from 1865 as the Yokosuka Iron Works, a shipyard built with French assistance under the engineer Léonce Verny, renamed Yokosuka Navy Yard in 1871 and reorganised from 1886 by Louis-Émile Bertin. It became a principal arsenal of the Imperial Japanese Navy, with shipbuilding, gun and ordnance plants, fuel storage, a seaplane base and a naval air station. The U.S. Navy assumed control on 30 August 1945 and Commander Fleet Activities Yokosuka was created shortly afterwards; the shipyard was initially deactivated before its shops and dry docks were reactivated in 1947 for U.S. Pacific Fleet ships.