During the Middle Ages, Wil Castle was built near the village and it became the seat of the Herrschaft of Schlosswil. The lords of the fort, the Freiherren von Wiler, were first mentioned in 1146. The von Wiler family died out around 1300, and the village and associated territory passed through several noble families, including the Freiherren von Signau and eventually the Senn von Münsingen family. The territory was split in half and passed through several Bernese patrician families until Burkhard von Erlach reunited the two halves in 1514.
In 1546 the medieval castle was destroyed in a fire. Shortly thereafter it was rebuilt as a larger castle under the direction of the master builder Niklaus von Wattenwyl-May. The current appearance comes from a 1780 renovation that gave the castle a Baroque exterior.
Following the 1798 French invasion, under the Helvetic Republic the nobility lost much of their power and property and by 1812 the castle was acquired by the Canton of Bern. In 1818 the castle tower became the only granary for the district of Konolfingen. A famine in 1816-17 was partly alleviated by the grain at the castle. In 1847 the tower was converted into a prison, a role that it filled until 1881. Even after the prison closed, the castle continued to be used by the district administration and courts. In 2010 the District of Konolfingen was dissolved and the need for district offices vanished. In 2011 it was acquired by Matthias Steinmann, who founded the Steinmann Foundation to operate the castle.
The original fortress tower was built in first half of the 12th century for the von Wiler family. The walls of the square tower are 38 meters tall and to the peak of the roof is 43.5 meters.
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.