The Diocesan Museum is located in the rooms of the convent of Sant Agusti, also known as El Socors. The current ensemble was built in the 17th century, although records show there was a convent back in the 15th century in Ciutadella, hard pressed by attacks by the Turks (1588). After seizure and sale of Church property in the mid-1800s, its Church, which was noted for the frescos on the vaulted ceiling, was given to the Seminary. After the destruction caused by the Spanish Civil War, the decision was taken to use it as home of the Diocesan Museum.
The museum has island-related pieces such as archaeological material, paintings and engravings from the 18th and 19th centuries and collections from the cabinet of Physics and Natural Sciences from the Diocese Seminary.
Currently, the rest of the convent is used for a variety of purposes. One wing is reserved for the nuns, but the rest is open to the public. Its library, its meeting rooms and even its accommodations are available for use. Furthermore, guided tours are available to visit the most relevant spaces of the building, such as the cloister. Concerts are held from time to time.