Cronk Howe Mooar is a motte and bailey castle from the late 11th or early 12th century. Steep sided, flat topped and grass covered, 30 to 35 feet high, diameter about 140 feet, surrounded by a well marked ditch which, on the east, cuts across a low spur projecting in that direction. There are faint traces of earthbanks in the wet ground east of the mound.
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.