Châteaugiron developed around its château from the 13th century onwards, becoming more prosperous towards the end of the Middle Ages as the canvas sail industry expanded. The town’s unique historic town centre is very well-preserved and features significant remains of the medieval fortress, renovated between 1450 and 1470 by Jean de Derval. Of the six original towers, four are still standing: the 38 metre high 13th-15th century keep, built independently of the château, the 14th-15th century clock tower, a belfry during the French Ancien Regime, and the 15th century watchtower and Cardinal’s tower, whose elevated patrol paths with machicolation projections has been preserved.
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.