The Ipf is a mostly treeless mountain (668 metres)with a prehistoric hill fort on its top. The fort is situated on an isolated hill, with a flattened summit surrounded by a stone wall, ditch and large counterscarp (outer bank). The overall diameter is about 180 metres. There are also extensive ramparts traversing the slopes to protect a large enclosed area and entranceway. There is evidence of occupation from the Bronze Age through the Iron Age to the early Celtic La Tene period, a span of almost a thousand years (1200 BC - 300 BC).
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.