Old San Juan The Spanish colonial district of San Juan is located on a small island on the north coast and contains numerous popular tourist sites, such as 17th and 18th century forts, fountains, plazas, and other historic buildings.

Fort San Felipe del Morro Constructed in the 16th century by the Spanish to guard the entrance to the port of San Juan, the fortress known colloquially as el Morro survived bombardments by foreign forces (including a fleet led by Sir Francis Drake) over multiple centuries. The fort is now a UNESCO World Heritage Site as well as a US National Park and serves as a major tourist attraction in the historic district of Old San Juan.

Fort San Cristóbal- The largest fortification ever built by the Spanish in the New World, El Castillo de San Cristóbal was completed in the late 1700's and guarded the land entrance to San Juan against invasion. Now a UNESCO World Heritage Site, the fort now serves as a museum and attracts millions of visitors each year.

Fortín San Juan de la Cruz Better known as "el Cañuelo," the smallest of the three island forts in the harbor of San Juan was built to guard the mouth of the Bayamón River while providing crossfire with the batteries of the larger El Morro fortification across the bay. Like its sister fortresses of El Morro and San Cristóbal, el Cañuelo is now a UNESCO World Heritage Site.

Plaza de Armas Located on San José Street, this picturesque square in Old San Juan is the site of the City Hall and contains numerous historic statues as well as a round fountain known as "The Four Seasons."