Casa Blanca Museum

Built in 1521 as the intended residence of Juan Ponce de León, Casa Blanca outlasted its original purpose before it could begin: de León died before ever living there. His descendants occupied it until the mid-18th century. The structure served as a Spanish military post, then passed to the U.S. military after 1898, before the Puerto Rican government designated it a historic monument in 1967. It now operates as a museum of 16th- and 17th-century artifacts, administered by the Institute of Puerto Rican Culture.