Between 1947 and 1992 the US Navy operated Subic Naval Base, which became the busiest naval port in the Pacific and was America's largest naval installation outside the United States.

The increasing importance of the naval base manifested itself as it provided support to the US Navy in its various military campaigns in the region: in the 1950's during the Korean war, in 1960's during the Vietnam war and more recently during the Gulf war of 1991. Aside from naval operations, the base was used for jungle survival and maritime operation training. During the 1960's and 70's the recreational facilities were developed and enhanced, the Subic Bay - with its sprawling and spectacular beaches - became the premier rest and recreation destination ib the Far East for naval personnel and their families.

The expiry of 1947 Military Bases Agreement in 1991 brought about the total withdrawal of the American forces by the end of 1992. Conversion of the former naval base into a self-sustaining commercial, industrial and financial investment haven is being undertaken by the Philippine government.