Coloma castle was built around 1515. It is a square building with square corner towers and a pear-shaped roof and surrounded by a moat. The castle has been completely restored and serves as a municipal cultural center. In the castle park are some interesting buildings such as the former carriage house of 1731 (now a cozy tavern) and a garden pavilion with stair tower. The Rose Garden of Coloma is the largest in Europe. The garden has an area of 15 hectares.
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.