Old San Juan (Spanish: Viejo San Juan) is the oldest settlement within Puerto Rico and the historic colonial section of the city of San Juan. Old San Juan is located on a small and narrow island which lies along the north coast, about 35 miles (56 km) from the east end of Puerto Rico, and is united to the mainland of Puerto Rico by three bridges. In 1508, Juan Ponce de León founded the original settlement, Caparra (named after the Province of Cáceres, Spain, birthplace of the then-governor of Spain's Caribbean territories, Nicolás de Ovando). Constructed in 1521, Casa Blanca served as the first fortification of the settlement and residence of Juan Ponce de León descendants, until the mid-eighteenth century. In 1509, the settlement near the fort was abandoned and moved to a site which was called at the time "Puerto Rico" (meaning "rich port" or "good port”). In 1521, the name "San Juan" was added, and the newer settlement was given its formal name of "San Juan Bautista de Puerto Rico", following the usual custom of christening the town with both its formal name and the name which Christopher Columbus had originally given the islands, honoring John the Baptist. the San Juan National Historic Sites were declared a World Heritage Site by UNESCO in 1983.