The former collegiate church of the Benedictine order, today the Catholic parish church, received the relics of Saint Chrysanthus and Daria in 844. Building was begun in the mid-11th century and completed in the 12th century. It is a romanesque, three-nave buttressed basilica without a transept, with west work and long chancel, as well as an important crypt. Restoration work has been carried out from 1876 to 1893 and since 1957. The interior of the church is well worth seeing.
References: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.