Kalmar Church was built of granite in the late 12th century. Around 1300 it was enlarged and modified to the aisleless Gothic church. In 1485 famous Albertus Pictor decorated walls and vaults with murals. Frescoes were restored in 1958 and still visible. Th current tower was added in 1830. There is font with a cuppa, made of red sandstone, from the late 1100s and medieval wooden sculptures (like a triptych from the mid-1400s) in the church.
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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.