Fort San Felipe del Morro --or El Castillo San Felipe del Morro in Spanish-- is a sixteenth-century citadel which lies on the northwestern-most point of the islet of San Juan, Puerto Rico. Named in honor of King Philip II of Spain, the fort, also referred to as &quot;El Morro&quot; or &quot;promontory&quot;, was designed to guard the entrance to San Juan bay, and defend the city of San Juan from seaborne enemies..In 1983, the fort was declared a World Heritage Site by the United Nations and is part of San Juan National Historic Site. Over two million visitors a year explore the windswept ramparts and passageways making the fort one of Puerto Rico's main visitor attractions...