St Mary's Church is dated mainly to the 14th century, though significant alterations were added in the 16th century. The tower dates to the latter period. The church was extensively renovated by J. Pritchard and J.P. Seddon in 1860. The eastern stained class windows were added by Morris & Co. P.S. Webb was responsible for the patterns while the figures are the work of P.P. Marshall. Among the depictions on these windows are Christ saving Peter from drowning in the sea, Christ miraculously curing a woman, and Thomas the Doubter. The octagonal font dates to the 19th century, while the pulpit was installed in 1942.
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.