Cartagena has more to do than most visitors can fit into a short stay. The walled city is a UNESCO World Heritage Site and best explored on foot — walk the city walls, look closely at the colonial door knockers, and allow time to get lost in the residential lanes of San Diego.
The Castillo de San Felipe de Barajas is the most impressive fortress in the Spanish Americas and should not be missed. The Palace of the Inquisition and the Iglesia de San Pedro Claver round out the essential historical sights. For panoramic views, take a taxi up to Convento de la Popa.
Outside the city, day trips to the Islas del Rosario for snorkelling, Playa Blanca for the best Caribbean beach, and the Volcán del Totumo mud baths are all popular. The early morning hours are the best time for sightseeing before the heat sets in.