The colossal Heidenreichstein castle situated in the moorlands to the northwest of the Waldviertel is the largest and best preserved medieval water castle in Lower Austria. The oldest parts of the castle are dated back to the 12th century. It has never been in enemy hands since its construction. The walls of the four wings, the three corner turrets and the keep are up to four metres thick. A guided tour through the three-storey living apartments with spiral staircase and arcades discloses highly remarkable interior fittings including Gothic furniture, articles of daily life and portrait paintings.
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.