The construction of the Klingnau castle, originally the seat of the Klingen family, was started in 1240. Until 1269 a manor house stood on the grounds. After 1331 the outer walls were added. In the second half of the 14th century the Bishop of Constance was often a resident in the castle. He ordered further improvements and expansions.
In the late 16th century, the castle, which was the seat of the bailiff from Constance, in such bad condition that the Swiss Confederation demanded a renovation from the bishop. In 1804 the castle went to the newly formed Canton of Aargau, who auctioned it off in 1817. As a result it has been used by various industries, until the 20th century when it was taken over by a foundation.
References:Saint-Georges de Boscherville Abbey is a former Benedictine abbey. It was founded in about 1113 by Guillaume de Tancarville on the site of an earlier establishment of secular canons and settled by monks from the Abbey of Saint-Evroul. The abbey church made of Caumont stone was erected from 1113 to 1140. The Norman builders aimed to have very well-lit naves and they did this by means of tall, large windows, initially made possible by a wooden ceiling, which prevented uplift, although this was replaced by a Gothic vault in the 13th century. The chapter room was built after the abbey church and dates from the last quarter of the 12th century.
The arrival of the Maurist monks in 1659, after the disasters of the Wars of Religion, helped to get the abbey back on a firmer spiritual, architectural and economic footing. They erected a large monastic building one wing of which fitted tightly around the chapter house (which was otherwise left as it was).