Castillo San Cristóbal

Things to do · San Juan, Puerto Rico

The largest fortification the Spanish built in the Americas, completed in the 18th century to defend San Juan from land attack. Its layered outworks, dry moats and long tunnels are fascinating to wander, and the upper batteries give sweeping views over the old city's rooftops and the Atlantic. Together with El Morro it forms the San Juan National Historic Site, and a single admission covers both fortresses, an easy walk apart along the city walls.