The Fortress-Castle is located at Plaza Glorieta. It is a good example of Renaissance military architecture of the 16th century and was designed by Juan Bautista Antonelli in 1553 for Bernardino de Cardenas, who was the Viceroy of Valencia. It was meant to stop Berber pirate attacks along the Mediterranean coast. In 1859 the City Hall took ownership of the castle and used it for civil functions.

Today it is used as the City Hall and the Guardia Civil Headquarters, as well as a Cultural Center that contains the Maritime Museum, the Fishing Museum, the Exhibition Hall, the Duke of Arcos Bastion and the Virgen de Loreto Chapel.