Fortaleza la Polvora
Fortaleza de la Polvorais currently a museum housing military artifacts and some art. The fort was originally built in 1748 to protect the city's gunpowder supply and ward off pirates. It has five towers connected by stone walls and the main gate consists of large oak doors. You are able to climb up one of the towers to get a better view of the city. The fort is free to walk around and enjoy and it doesn't really have defined operating hours.