The Old Capitol Building or The Castle, as it is locally known, is a building in Olympia, Washington. Designed by Willis A. Ritchie, it was built 1890–1892 as the Thurston County Courthouse, and served 1905–1928 as the state capitol, seat of the legislature of Washington; in 1928 the legislature moved to the current Capitol Building. It is now the office of the Superintendent of Public Instruction.