[9] In 1868, a Spanish military expedition was dispatched to study the possibility of relocating the Cavite Naval Station in Subic Bay due to its unhealthy condition.

Spanish King Alfonso XII through a Royal Decree made Subic Bay (then called Subig) as Spain's stronghold in the Far East in 1884.

The Spanish planned to transform their naval station and the village of Olongapo into an island, safeguarding it from potential rebel attacks.

On May 1, 1898, the construction of the Spanish Administration Building was nearly complete when Admiral Dewey's flagship, USS Olympia, led the Asiatic Fleet into Manila Bay.

The promise of a different kind of experience as shop workers and office help induced many young men to leave their farms and fishing boats to work in the Navy Yard.

[14] When the American forces made a last-ditch stand on the Bataan peninsula, the Naval Station was abandoned and most of its facilities were burned before the Japanese came.

Joint American and Philippine Commonwealth ground troops aided guerrilla fighters in liberating Olongapo from the Japanese forces.

[10] Gradually, Olongapo evolved into a new community: new businesses were established, housing projects were planned and civic facilities were restored.

During the Korean War, the United States spent over US$170 million to convert the base into the homeport of the Navy's Seventh Fleet, developing the Cubi Naval Air Station as the largest US installation of its kind in Asia.

[10][17] On December 7, 1959, 56,000 acres of land with electrical, telephone and water utilities was relinquished to Philippine Secretary of Foreign Affairs Felixberto Serrano.

[citation needed] The beginning months of the 1970s marked a period of turmoil and change in the Philippines, as well as in Olongapo and Zambales.

[18][19] During his bid to be the first Philippine president to be re-elected for a second term, Ferdinand Marcos launched an unprecedented number of foreign debt-funded public works projects.

[citation needed] The base was visited by 215 ships per month as the Vietnam War peaked in 1967, and it employed 15,000 Filipino civilians.

[31] The policies of the Marcos administration encouraged the growth of the sex-industry[32]: 128  because it increased the flow of higher value currency into the Philippine economy.

[33]: 13 The economies of Olongapo and the nearby areas of Zambales evolved from a largely agricultural orientation at the end of the 1960s[32][33] towards one built around sex industry related businesses such as bars by the mid-1970s.

[30] Sailors' accounts recall the popularity of musical performances, inexpensive San Miguel beer, attractive teenage prostitutes, erotic floor shows, Jeepney rides back to the naval base and children diving for coins tossed from the bridge over the estuarine drainage channel in front of the naval base main gate were popular amenities among the sailors.

Volcanic earthquakes and heavy muddy rain, as well as thunderstorms from a typhoon passing over Central Luzon, darkened the area for 36 hours in what would become known as "Black Saturday".

Olongapo surged to national prominence during the incumbency of Mayor Richard Gordon, who, like his father before him, was against the departure of US military forces, yet lobbied for the turnover of the facility and its conversion into a freeport in 1992.

Gordon spearheaded a volunteerism strategy to return an ailing economy to prosperity after Mount Pinatubo's eruption and the withdrawal of US forces.

The strategy worked across all demographics and involved a strong corps of 8,000 volunteers who protected and preserved the abandoned base facilities from poachers.

[17] A recent racial study showed that Angeles City, Pampanga; alongside Manila; and Olongapo, Zambales; was the locations of several concentrations of 250,000 Amerasians (Mixed American-Asians) who were born as a result of the American colonization of the Philippines and the presence of US bases in the country.

The city proper is located on 6.48 square kilometers (2.50 sq mi) of tidal flatland, with the rugged Zambales Mountains on its three sides, and Bataan and Subic Bay at its base.

The months of December to April are extremely dry but the wet season persists for the remaining period in a year.

The city's population speaks a wide array of the nation's main languages, specifically: Tagalog, Sambal, Kapampangan, Pangasinan and Ilocano.

The airport is within the Subic Bay Freeport Zone and was formerly known as Naval Air Station Cubi Point, when it was still an airbase of the United States.

Some facilities of the seaport are located on the Olongapo portion of the Subic Freeport Zone namely the Alava, Bravo, and Rivera Wharves.

In the city's main district, the names of those streets running from North to South follow the English alphabet's order.

All public utility jeepneys and tricycles have its own color code depending on the district, zone or route that it is serving.

Local bus terminals are also present and are primarily used for transportation in neighboring towns and inside the Subic Bay Freeport Zone.

Then Mayor James Gordon Jr. also attributed the crisis to low collection rate due to nonpayment or debts incurred by consumers, widespread energy theft and corruption in the PUD.