Montemayor del Río Castle probably doesn't date back to before the 15th century, and has more the character of a palace than of a strength. It has two existing enclosures. From the outer one only the entrance, flanked by two turrets, remains. The inner has an irregular groundplan, adapted to the outline of the land it was build on.
In the interior two floor levels can still be traced which were arranged around a central patio. In the left wall a large chimney is conserved, evidence of habitation.
The Château de Foix dominates the town of Foix. An important tourist site, it is known as a centre of the Cathars. Built on an older 7th-century fortification, the castle is known from 987. In 1002, it was mentioned in the will of Roger I, Count of Carcassonne, who bequeathed the fortress to his youngest child, Bernard. In effect, the family ruling over the region were installed here which allowed them to control access to the upper Ariège valley and to keep surveillance from this strategic point over the lower land, protected behind impregnable walls.
In 1034, the castle became capital of the County of Foix and played a decisive role in medieval military history. During the two following centuries, the castle was home to Counts with shining personalities who became the soul of the Occitan resistance during the crusade against the Albigensians.