6 contributing buildings. 1 contributing site. Added to the National Register of Historic Places October 15, 1966. Kawaiahaʻo Church is a historic Congregational church located in Downtown Honolulu on the Hawaiian Island of Oʻahu. The church, along with the Mission Houses, comprise the Hawaiian Mission Houses Historic Site, which was designated a U.S. National Historic Landmark (NHL) in 1962. In 1966 it and all other NHLs were included in the first issuance of the National Register of Historic Places. At one time the national church of the Hawaiian Kingdom and chapel of the royal family, the church is popularly known as Hawaiʻi's Westminster Abbey. The name comes from the Hawaiian noun phrase Ka wai a Haʻo (the water of Haʻo), because its location was that of a spring and freshwater pool in the care of a High Chieftess Haʻo. Today, Kawaiahaʻo continues to use the Hawaiian language for parts of the service. It is one of the oldest standing Christian places of worship in Hawaiʻi, although four thatched churches stood at or near the present site before construction of the coral church. The oldest standing church is Mokuaikaua Church on the Big Island. Denominationally, It is a member of the United Church of Christ.(read more...) National Park Service documentation: https://npgallery.nps.gov/AssetDetail/NRIS/66000294