Discovery of the bay

The discovery of Subic Bay is credited to the Spanish conquistador Juan de Salcedo, grandson of Miguel Lopez de Legaspi – the explorer who established Spain’s control and dominion over the Philippines. It was during a visit to the province of Zambales to collect tributes for the Spanish Crown from the natives in the area that Salcedo recognized Subic Bay’s potential as a strategic naval base.

Spanish Arsenal (Spanish Gate)

However, it wasn’t until the British occupation of Manila in 1762, when they had to temporarily transfer their fleet from their main naval base, that the Spanish Navy actually considered making Subic Bay into an operational harbor.

The main Spanish naval base at the time was located in Cavite along Manila Bay. Extremely poor living conditions and inclement weather in the area, worsened by malaria and the unchecked growth of other diseases, forced the Spanish forces to conduct a military expedition to Subic Bay in the hopes of determining a specific site for their new headquarters.

As a result of the expedition, a naval decree was issued by King Alfonso II in 1884 pronouncing Subic Bay as “a naval port and the property appertaining thereto set aside for naval purposes”. In 1885, more than 340 years after Salcedo first laid his eyes upon Subic Bay, work was started in earnest to transform the area into a Spanish naval station.

The Spanish Fleet, using local labor, dredged the harbor basin, built a drainage canal surrounding the port making an “island” for the Spanish Navy Yard. The canal reduced disease by draining the swampy terrain and also served as a defensive barrier around the base. The canal still exists today surrounding the Subic Bay Freeport and crossed by bridges into Olongapo City.

The locals, working in lieu of tax payments, built several seawalls, causeways and a railway line was constructed over the tidal flats bordering the Navy Yard. These projects required quarrying thousands of tons of dirt and rock from the Kalalake area of Olongapo. The former quarry area is now a lagoon and can be located at the Bicentennial Park in the Subic Bay Freeport.

When the Spanish Arsenal was finished, the gunboats Caviteno, the Sta. Ana, and San Quentin were assigned to its defense — complemented by gun batteries on the station and on Grande Island at the mouth of the bay.