I’m not an expert, but I believe there are only two historical landmarks at the Subic Bay Freeport Zone. The “island” part of the freeport zone was occupied by the Spanish Navy until 1898, the end of the Spanish-American war. It was taken over by the US Navy until it was turned over to the Philippines in 1992. US Naval Base Subic Bay was held by the Japanese Navy during the Japanese occupation of World War II.
There are multiple entrances (bridges and gates) to the freeport zone. The easiest way to get to these landmarks, however, is to use the Kalaklan Lighthouse Bridge from National Highway. From there, travel on Dewey Avenue and look to your left. The first landmark is the chapel.
When the “village” of Olongapo was still on the “island”, the place of worship was called the Olongapo Parish Church.
It became the US Navy’s base chapel until the base was closed and then it was renamed as the San Roque Chapel.
If you continue to the end of Dewey Avenue, you can see the Spanish Gate directly ahead of you.
This was the western entrance to the Olongapo Arsenal when the Spanish controlled the freeport zone. Everything east of the gate was Olongapo.
Olongapo was destroyed twice during World War II. At the end of war, the base was extended to National Highway and Olongapo was relocated to the other side of the river.
The are other places of interest at the freeport zone, but no other landmarks that I know about. Of course, the “island” part of the freeport zone is only a small part of the entire freeport zone. if you browse to Google Maps and enter “Subic Bay Freeport Zone, Central Luzon, Philippines”, you can see how big the freeport zone really is.
Considering the history and the changes of the area in and around the Subic Bay Freeport Zone, I’m surprised anything remains to remind people it was involved in three different wars: The Spanish-American War (1898), the Philippine-American War (1899–1902) and World War II (1939 to 1945).