Castillo San Felipe de Barajas

Castillo San Felipe de Barajas is the fortress that sums up why Cartagena was so hard to take. It sits on the Cerro de San Lázaro, a hill about 41 metres above sea level just east of the walled city, and its job was to stop attackers who had landed and were advancing by land. Work began in the 17th century, when it was known as the Castillo de San Lázaro; it was later renamed after Philip IV of Spain. It was built by enslaved African labourers under Spanish supervision, and the military engineer Antonio de Arévalo directed a major expansion in 1763. Escuela Taller Cartagena de Indias, which runs the city's fortifications, still calls it "el inexpugnable".

Its history is a long list of sieges. The French privateer Baron de Pointis captured it in 1697, but in 1741 the British admiral Edward Vernon failed to take Cartagena during the War of Jenkins' Ear, with the Spanish commander Blas de Lezo leading the defence. Together with the rest of the city's fortifications, the castle has been part of a UNESCO World Heritage Site since 1984.

The visit is a climb through ramps, gun platforms and batteries with names such as Santa Bárbara, San Carlos y Los Apóstoles and La Redención. The walls were built thick at the base and narrower at the top so that each battery could cover its neighbours. Beneath them runs a network of tunnels and galleries, some designed to be blown up under attackers; only part of the tunnel system is open, and the operator warns that some passages can be slippery. Night tours of the illuminated fortress are sometimes offered, and from the top there are panoramic views over the city.

The castle is open every day from 07:00 to 18:00. Tickets can be bought online, which helps you skip the queue, and guides are not included in the ticket but can be hired at the ticket office. Entry is free for visitors with a notable disability and one companion. Expect steep ramps and stairs, so wear comfortable shoes. The heat can be intense around midday, so an early start, sun protection and plenty of water are sensible, especially with children or older visitors. Pets are not allowed apart from guide dogs.

The fortress is on Avenida Antonio Arévalo in the Pie del Cerro sector, about 10 minutes by car from the Torre del Reloj and roughly 15 minutes from Rafael Núñez International Airport. There is parking on Avenida Antonio Arévalo and on Calle 31 near the Botas Viejas monument. Allow two hours, and combine it with Getsemaní, the walled city or the Convento de La Popa above it.