This castle held the Coyanza Council in 1050; the old Coyanza was populated and fortified by Fernando II of León in the second half of the 12th century. The current castle was built in the 15th century. It was constructed on the site of older castle that had been erected on the ruins of a fortification dating back to the Iron Age.
The castle consists basically of one articulated front with projections, flanked by turrets overshadowing the tower of homage, with round turrets in the Gales and fronts.
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.