Cartagena

Colombia's crown jewel is a perfectly preserved 16th-century walled city on the Caribbean coast, a UNESCO World Heritage Site whose pastel colonial buildings, bougainvillea-draped balconies, and cobblestone streets have appeared in Gabriel Garcia Marquez novels and countless films. The city's 11-kilometre defensive wall, built by Spain between 1586 and 1796 to protect its South American gold port, is one of the most complete fortifications in the Americas — 30% longer than the walls of Old San Juan and visited by over 4 million tourists annually.