A gorgeous fishing village on Colombia's Caribbean coast, Cartagena is a veritable treasure trove of colonial architecture and 17th-century forts. One of the safest spots in the country, this cruise ship call favorite boast many fine beaches, great restaurants and an entirely walkable historic old town. Don't miss the lovely Walled City, Plaza Bolivar (home to Palacio de la Inquisicion), the cathedral and a gold museum. And San Felipe de Barajas Castle, one of Colombia's oldest buildings.