Kamehameha V Post Office, 46 Merchant St.
The Kingdom of Hawaii organized its own postal system in 1851, and under the pressure of Postmaster General A.P. Brickwood, King Kamehameha V authorized an office built out of concrete blocks and iron bars, then an experimental construction method in Europe and unheard of in Hawaii. According to an application filed in 1972 to the National Register of Historic Places, the Post Office is the oldest concrete structure in Hawaii, possibly in America. In its history, the building has also housed the publishing and printing facilities for the Hawaiian Gazette, a drivers’ education office, Honolulu District Courts and, since 1993, the Kumu Kahua Theatre.