Honouliuli National Historic Site

Honouliuli National Historic Site is near Waipahu on the island of Oahu, in the U.S. state of Hawaii; it is the location of the Honouliuli Internment Camp, Hawaiʻi's largest and longest-operating Japanese internment camp, which opened in 1943 and closed in 1946. The site was designated a national monument on February 24, 2015, by President Barack Obama. The John D. Dingell, Jr. Conservation, Management, and Recreation Act, signed March 12, 2019, redesignated it as Honouliui National Historic Site.

The internment camp held 320 internees. In Hawaii, where more than 150,000 Japanese Americans comprised more than one-third of the territory's population, only 1,200 to 1,800 were incarcerated. The site also became the largest prisoner of war camp in Hawaiʻi with nearly 4,000 individuals being held. Of the seventeen sites that were associated with the history of internment in Hawaiʻi during World War II, the camp was the only one built specifically for prolonged detention.

As of 2015, the national monument is without formal services and programs.