In the 13th century, the town of Kadaň was promoted to a 'Royal City'. It began to thrive and a new town was built on the heights above the river, with a castle and Franciscan monastery. The castle was mentioned first time in 1289. It was established as a four-wing Premyslid castle with a housing palace over the river. It served as the seat of the royal burgrave – the administrator of the Kadan region.
The castle was rebuilt in the mid-15th century. After it had been damaged during the Thirty Years Wars, Maria Therese allowed it to be rebuilt as military quarters in 1750. The eastern wing is used for the municipal library with an internet cafe and ceremonial hall. The Josef Liesler Gallery has been in operation since September 2000. A nursing home is situated in another part of the castle.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.