Sipoonlinna (Sibbesborg) was a medieval castle made of stone and wood. It was probably built in the 14th century as part of the fief system created by Albrecht von Mecklenburg. Regarding folklores castle was founded by viking Sibbe (Sighbion) or Danish crusaders in the 12th or 13th century. Nowadays only some earth walls remain on the forested hill upon which it stood. The site can be accessed on foot.
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.