Saint Eilian's Church is Grade I listed Celtic church, with a 12th-century tower, 14th-century chapel and a nave and chancel dating from the 15th century. In the chancel is a 15th-century rood screen, and there are traces of post-medieval wall paintings. A painting of a skeleton bears the inscription Colyn angau yw pechod ('The sting of death is sin'). The Church is named after Saint Eilian (Eilianus). Eilian of Rome also known as Eilian of Anglesey was a 6th-century saint who came from Rome to Britain where he lived as a hermit in the area north of Anglesey. His feast day is 13 January. The churchyard contains the war grave of a Royal Navy sailor of World War I.
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.