The Casa Blanca (White House) was built in 1521 and lived in by Ponce de Leon descendants for over 250 years. In 1779 it was taken over by the Spanish military, then used later by the United States as a residence for military commanders (1898-1966). Today the mansion serves as a National Historic Monument, housing a museum of 16th, 17th and 18th century history. Each room is decorated in a style associated with a period of the house's history. Casa Blanca is the oldest continuously occupied residence in the Western Hemisphere. Located at 1 Calle San Sebastian Street, Old San Juan, it houses an ethnographic museum and Taino (native Indian) artifacts.