Subic Bay is a bay on the west coast of the island of Luzon in the Philippines, about 100km northwest of Manila Bay. It is a successful industrial and commercial area known as the Subic Bay Freeport Zone under the Subic Bay Metropolitan Authority .
Subic Bay is surrounded by Olongapo City, the town of Subic and the Subic Bay Freeport Zone, both in the province of Zambales. Development of Olongapo City was largely tied to the presence of the United States Navy base at Subic Bay, once the largest U.S. military base in Asia. An arsenal and ship-repair facility was established at Subic Bay in 1885 by the then colonial power, Spain. Following the Spanish-American war of 1898–1899, Subic Bay became a U.S. Navy and Marine base, and grew to be a major facility.
In 1991, the Philippine Senate rejected terms for renewal of the lease of the base. After nearby Mount Pinatubo erupted, the base closed and the last ships left in 1992.
The impact of the U.S. Navy on Subic Bay and Olongapo City was the subject of a controversial book, One of the Guys, by American author Robert Clark Young in 1999.