Hardegg Castle was first mentioned in an 1145 deed, it was acquired by the Counts of Plain about 1187. Hardegg itself is first documented as a town in 1290. Located on the border with the Kingdom of Bohemia, the area was devastated during the Hussite Wars in 1425. In 1483 Hardegg was bequeathed to the Habsburg archdukes of Austria.
Emperor Maximilian I granted Hardegg to his ministeriales of the Prueschenk noble family and elevated them to immediate Counts of Hardegg in 1499. Two years later Count Ulrich purchased the Bohemian County of Kladsko from the Dukes of Münsterberg. From the Thirty Years' War onwards the castle decayed, until it was acquired by the Khevenhüller dynasty and rebuilt in the late 19th century according to plans designed by Carl Gangolf Kayser.
After World War II until the fall of the Iron Curtain, Hardegg was particularly isolated. The only connection to the Czech Republic is via a bridge built in 1874 across the Thaya to the neighbouring village of Čížov.
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.