Fodor's Expert Review Castillo de San Felipe de Barajas

What began in 1657 as a small fort designed to protect the overland entrance to Cartagena grew over the following century into a sprawling stone behemoth covering the entire hill. Spanish military engineer Antonio Arevalo presided in 1762 over the defining phase of construction that would leave the fort much as it is seen today, the largest of its kind on the continent and a fascinating example of asymmetrical military construction unseen in Europe. The unique layout allowed for devastatingly efficient lines of coverage for some 63 cannons lining the walls, and the fort would never fall. In addition to the cannons, another of his ingenious devices was a maze of tunnels—minimally lit today to allow for spooky exploration—that connects vital points of the fort. Notice the near-perfect acoustics here: occupants could even hear the footsteps of the approaching enemy. If you don't speak Spanish, an English audio guide (10,000 pesos) makes the visit infinitely richer. The fort is an easy enough walk from Getsemaní with great views of the city; the best time to go is in the afternoon. A taxi shouldn't cost more than the standard minimum 6,000 pesos, although most drivers will want to charge you 8,000. READ LESS