Castillo San Felipe de Barajas

Castillo San Felipe de Barajas is a Spanish colonial bastion fortress on San Lazaro Hill overlooking Cartagena, Colombia, begun in 1536 and expanded in stages through 1767, with a major enlargement directed by the military engineer Antonio de Arevalo starting in 1763. Built largely by African slave labor under Spanish supervision, the fortress took a triangular form with eight batteries, among them Santa Barbara, San Carlos and Los Apostoles, mounting a combined 68 guns trained on the harbor approaches. Its interior is honeycombed with a network of tunnels at sea level, some fitted with underground chambers designed to be detonated beneath attackers who breached the outer defenses. UNESCO listed the castle as a World Heritage Site in 1984 alongside the historic center of Cartagena. It now hosts cultural events, presidential summits and international conferences alongside its ordinary role as a visitor attraction, with several tunnel sections open for public viewing.