US Army Museum of Hawai'i

The US Army Museum of Hawai'i traces the military history of consolidation of power under King Kamehameha in the 1700s to the US army's ongoing role on the island. Located at Fort DeRussy Military Reservation, the museum occupies Battery Randolph, a reinforced concrete building erected in 1911 as a coastal artillery battery.

The battery once held two formidable 14-inch disappearing guns with an 11-mile range, designed to recoil into the concrete walls for reloading after firing, which shook the whole neighborhood. A 55-ton lead counterweight then returned the carriage to position. Also on display is a Cobra helicopter and various military tanks and machinery. On the 2nd floor of the complex is the Pacific Regional Visitor Center, which documents the flood-control and water-management projects of the US Army Corps of Engineers in Hawaii. The surrounding area is part of Fort DeRussy, a US army post used mainly as a recreation center for the armed forces. This large chunk of Waikiki real estate was acquired by the US army a few years after Hawaii was annexed by the USA. Prior to that it was swampy marshland and a favorite duck-hunting spot for Hawaiian royalty. The Hale Koa Hotel on the property is open only to military personnel, but there's public access to the beach and the adjacent military museum. The section of Fort DeRussy between Kalia Rd and Kalakaua Ave has public footpaths that provide a shortcut between the two roads.