The Liebenstein Castle , now a ruin , is on a granite cone north of Plößberg. The hill fort was first mentioned in 1125. In 1292 the family who built the Liebenstein family died out and the castle was sold by Theodorich von Parsberg to the abbot Theoderich of the Waldsassen monastery in 1298 . Theodoric carried out extensive repairs , and the castle was given an outer wall under Abbot Franz Kübel . With the abolition of the monastery during the Reformation, the castle was sold to the Tirschenreuth citizen Anton Mehler and his descendants. After 1634, after it had previously been the seat of the judges' office, it was no longer inhabited and fell into disrepair.
On granite cone of Castle Hill were up in the 1950s several quarries, are also obtained immediately below the ruins themselves. Originaer few foundations of the keep , since the summer of 2007 parts are built up the walls again.
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.