Historic Kamehameha V Post Office Building

The Kamehameha V Post Office stands at the corner of Merchant and Bethel Streets as the oldest surviving public building in the United States constructed with reinforced concrete. Completed in eighteen seventy-one, the structure was the first in the Hawaiian Islands to use precast concrete blocks reinforced with iron bars, a pioneering building method that demonstrated enough durability for the government to later apply it to the royal palace, Aliʻiōlani Hale.