The site of current Seeburg castle was mentioned first time in 740 AD. The construction of current castle was started in the 11th century (around 1036). It was largely extended by Wichmann von Seeburg, later Archbishop of Magdeburg (1115-1192). The next renovations took place in the 14th and 15th centuries, when the castle was flanked by towers and a gatehouse under the rule of Counts of Mansfeld.
Later Seeburg was left to decay until the Counts of Ingenheim sold it in 1880 to the Wendenburg family. In 1923, Erich Wendenburg commissioned the architect Paul Schultze-Naumburg to completely restore the building in neo-Gothic style.
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.