San Juan, officially Municipio de San Juan Bautista (Municipality of Saint John the Baptist), is the capital and most populous municipality in the Commonwealth of Puerto Rico, an unincorporated territory of the United States. As of the 2010 census, it had a population of 395,326 making it the 46th-largest city under the jurisdiction of the United States. San Juan was founded by Spanish colonists in 1521, who called it Ciudad de Puerto Rico («Rich Port City»). Puerto Rico's capital is the second oldest European-established capital city in the Americas, after Santo Domingo, in the Dominican Republic. Several historical buildings are located in San Juan; among the most notable are the city's former defensive forts, Fort San Felipe del Morro and Fort San Cristóbal, and La Fortaleza, the oldest executive mansion in continuous use in the Americas.
Five centuries ago, San Juan was an impenetrable fortified city, today is considered one of the most welcoming and culturally rich destinations. Visitors are captivated by the enchantment of the island, its culture, the Old World wonders of Old San Juan, the amenities and entertainment of a modern city, and the tropical allures of of a Caribbean destination.
San Juan, capital city of Puerto Rico, is actually two distinct destinations that are five centuries apart, creating one of the most unique and easily accessible places to travel under the U.S. Flag. San Juan, the second oldest city in the New World, is a vibrant, warm, sunny, and happy place both day and night.