St. Quentin Cathedral in Hasselt was granted to a cathedral in 1967, but its construction began already in the 11th century. The first church was built inthe 8th century and rebuilt in Romanesque style in the 11th century. The cathedral construction continued several centuries. In the 15th century the choir was rebuilt. During the iconoclasm the tabernacle and statues, the altar lateral and the main altar were destroyed. The tower of the present church dates from 1725; it was restored in the 19th century.
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.