From the World Heritage inscription for the La Fortaleza and San Juan National Historic Site:
The main elements of the massive fortification of San Juan are La Fortaleza, the three forts of San Felipe del Morro, San Cristóbal and San Juan de la Cruz (El Cañuelo), and a large portion of the City Wall, built between the 16th and 19th centuries to protect the city and the Bay of San Juan. They are characteristic examples of the historic methods of construction used in military architecture over this period, which adapted European designs and techniques to the special conditions of the Caribbean port cities. La Fortaleza (founded in the early 16th century and considerably remodeled in later centuries) reflects developments in military architecture during its service over the centuries as a fortress, an arsenal, a prison, and residence of the Governor-General and today the Governor of Puerto Rico.
San Juan is the second oldest city in the Western Hemisphere after Santo Domingo, Dominican Republic. The old city of San Juan still has the feel of a Spanish Colonial city. The fortifications of the city are still mostly intact and served to defend the San Juan harbor. Tip: If you visit the old city of San Juan, make sure to stop by Carli’s Bistro and listen to former Beach Boy keyboard player Carli Munoz play jazz.
View the complete list of UNESCO World Heritage Sites in the United States.
View the list of all of the UNESCO World Heritage sites I have visited on my travels.