At the north end of La Caleta Beach is the Castle of Santa Catalina. This was one of the first defenses created by architect Cristóbal de Rojas after the city was pillaged in 1596. The fortress was finished two years later. The design includes a star-shaped layout protected by two bastions and a moat. The military also had a jail here. In 1693, the Chapel of Santa Catalina was built within the walls. Today, Castillo de Santa Catalina has a free museum with displays about the fortress. In the summertime there are concerts in the courtyard.