The Castle of Cabra was raised, within the walled enclosure in the North West of the present town, on a spot high enough to overlook the whole town. It is said that it had a central square surrounded by a strong wall with eighteen towers where eight or ten thousand men could march. At present, most of what remains, it is enclosed within the constructions of the present School of the Escolapias. Among the constructions we have been able to locate the wall, of which something more than half still remains and to track the rest until we were able to determine, quite accurately, the plant of the enclosure which must have been quadrangular, of about 76x47m. The thickness of the walls is about two meters and sixty centimetres, approximately. The fact that the rest of the walls- and possibly of towers are surrounded by modern constructions hinders their thorough study.
As far as the towers are concerned, we can say that two of them are well known, plus the location of other two, that were to the sides of the present front door to the enclosure. In the centre of the East wall and half way out is the tower of Homage. It is almost square shaped and it is more than twenty meters high. At about eleven meter above ground level there is a squared chamber with an eight sided vault ceiling with tubes in the angles. The other tower is located in the northwest angle. It is of squared plant, with the angle that looks to the interior of the chamfered enclosure. The lower part is massive and in the upper part there is a chamber with a barrel vault. It still keeps about ten meters of its height and its maximum surface on the plant is 6.5×6.3m.
Of the other two acknowledged towers there only remain their foundations upon which modern constructions have risen.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.