Over 170 governors of Puerto Rico have lived in La Fortaleza – it is the oldest continuously operating governor's residence in the Western Hemisphere. The original fortification was built to protect the entrance to San Juan Bay, but was judged to be inadequate for the purpose. Many modifications in varying architectural styles, including Baroque, Arabian, Gothic and neoclassical, have been made through the years. English-language tours are available on the hour. Proper attire is requested.