The Castle of Good Hope is the oldest surviving building in South Africa. Built between 1666 and 1679, this pentagonal fortification replaced a small fort of timber and clay built by Commander Jan van Riebeeck in 1652 upon establishing a maritime replenishment station at the Cape of Good Hope for the Dutch East Indian Company or better known as the VOC (Verenigde Oost-Indische Compagnie) On 26 April 1679 the five bastions were named after the main titles of Willem, the Prince of Orange. The Western Bastion was named Leerdam; followed in clockwise order by Buren, Katzenellenbogen, Nassau, and Oranje. In 1936 the Castle was declared a National Monument. As a result of an extensive, ongoing restoration and conservation program launched in the 1980's, the Castle of Good Hope remains the best preserved of its kind built by the VOC in regions where it had interests in previous centuries.Today, the Castle of Good Hope house the regional headquarters of the South African Army in the Western Cape, the famous William Fehr Collection of historic artworks, the Castle Military Museum and ceremonial facilities for traditional Cape Regiments.