It is an Artistic historic building since 1931. It was built between centuries IX and XII. It acts of an oval fence which strengthens the top of the hill of Muela for the defence of an Arab demographic payment.

In it, almorávides act as much as almohades.

The walls are crowned by ramparts. Several turns are turns of flanks, those more famous are the Alpéndiz tower or the Tower of monitoring, of Horca, Seven Windows and the one of the Virgins. Also Albarrana is the tower of Espantaperros, located in the Eastern part of the Fortress, one of the monuments most representative of Badajoz. It is a tower on eight sides and 30 meters height, it is perfectly preserved, recalls by its style to the tower of the Gold of Seville, the latter was posterior and used as model that of Badajoz. Albarrana means that the tower was located in front of the wall and was connected to it through an arc and a narrow corridor. With the end of the tower one added in his part higher another final improvement rose during the Christian time, of style mudéjar which still remains, and in which is to show a marvellous bell until the last century. The tower is not opened with the public.

Some of the characteristics of this Fortress are that construction is very well adapted to the accidents of the ground, and it thus obtains a greater capacity of defence. It is also particular by its doors in curve put in transverse fabric or in with the dimensions ones of the tower. Two are preserved: that of the Capital, with the western South and that of Alpéndiz, in the South East. Others were: Yelves O of carros, that of the River and Treason. And in the interior one finds the Tower of Sta. María.

In the wall, Badajoz was during years a flowering Arab population. Being given its frontier situation with Portugal it had a special importance so much at times of war, being strategic place, as at times of peace, to have a commercially privileged situation.

The Fortress had a large Library; in it one wrote the largest encyclopaedia of all that is Arab in Spain. At that time of the kingdom of Tarifa, it underlined the culture of the letters, sciences and arts.