Cuéllar Castle is conserved in good condition, and it has been built in different architectural styles between the 13th and 18th century. Much of the castle in the Gothic and Renaissance styles. The military building was extended and transformed in the 16th century, turning it into the palace of the Duke of Alburquerque. Among its historical owners, stands out Álvaro de Luna and Beltrán de la Cueva, as well as the successive Dukes of Alburquerque.
The Dukes of Alburquerque lived in this castle for centuries until they moved to Madrid to be close to the court. Thereafter their use of the castle was as leisure and holidays palace, abandoning the building slowly. At the late 19th century the castle was almost completely abandoned, and was victim of robberies. In 1938 was a political prison was settled within the castle, and after was established also a sanatorium for prisoners affected by tuberculosis. It was used as prison till 1966.
In 1972, the Department of Fine Arts carried out an intensive restoration, and made it the home of a Vocational Education school, which continues to this day.
References:The city walls of Avila were built in the 11th century to protect the citizens from the Moors. They have been well maintained throughout the centuries and are now a major tourist attraction as well as a UNESCO World Heritage Site. Visitors can walk around about half of the length of the walls.
The layout of the city is an even quadrilateral with a perimeter of 2,516 m. Its walls, which consist in part of stones already used in earlier constructions, have an average thickness of 3 m. Access to the city is afforded by nine gates of different periods; twin 20 m high towers, linked by a semi-circular arch, flank the oldest ones, Puerta de San Vicente and Puerta del Alcázar.