Château de Quéribus is a ruined castle in the commune of Cucugnan. It is one of the 'Five Sons of Carcassonne', along with Aguilar, Peyrepertuse, Termes and Puilaurens: five castles strategically placed to defend the French border against the Spanish, until the border was moved in 1659.
Quéribus was first time mentioned in 1021 when it was one of the main Barcelonan strongholds north of the Pyrenees.
It is sometimes regarded as the last Cathar stronghold. After the fall of Montségur in 1244 surviving Cathars gathered together in another mountain-top stronghold on the border of Aragon. In 1255, a French army was dispatched to deal with these remaining Cathars, but they slipped away without a fight, probably to Aragon or Piedmont - both regions where Cathar beliefs were still common, and where the Occitan language was spoken.
Quéribus is high and isolated. It stands on top of the highest peak for miles around. In 1951 restoration work on the turret began, and between 1998-2002 a complete restoration of the castle was undertaken: the castle is now accessible to visitors.
References:Celje Castle was once the largest fortification on Slovenian territory. The first fortified building on the site (a Romanesque palace) was built in the first half of the 13th century by the Counts of Heunburg from Carinthia on the stony outcrop on the western side of the ridge where the castle stands. It had five sides, or four plus the southern side, which was a natural defence. The first written records of the castle date back to between 1125 and 1137; it was probably built by Count Gunter. In the western section of the castle, there was a building with several floors. Remains of the walls of this palatium have survived. In the eastern section, there was an enclosed courtyard with large water reservoirs. The eastern wall, which protects the castle from its most exposed side, was around three metres thicker than the rest of the curtain wall. The wall was topped with a parapet and protected walkway.