Nassenfels castle dates from the 12th-13th century. The first reference to the castle is dated to 1245, when Count Gebhard III of Hirschberg was assassinated when he was besieging Nassenfels castle. The castle was reconstructed and enlarged later and the current appearance dates from c. 1400. The three towers were built by bishop Friedrich von Oettingen. Nassenfels was again restored in 1464 and 1699. in 1807 the castle was sold to private owners and used as a quarry.
Château de Niort is a medieval castle in the French town of Niort. It consists of two square towers, linked by a 15th-century building and dominates the Sèvre Niortaise valley.
The two donjons are the only remaining part of the castle. The castle was started by Henry II Plantagenet in the 12th century and completed by Richard the Lionheart. It was defended by a rectangular curtain wall and was damaged during the Wars of Religion. In the 18th century, the castle served as a prison.
The present keeps were the central point of a massive fortress. The southern keep is 28m tall, reinforced with turrets. The northern tower is slightly shorter at 23m. Both are flanked with circular turrets at the corners as well as semicircular buttresses. Each of the towers has a spiral staircase serving the upper floors. The Romanesque architecture is of a high quality with the dressed stones closely jointed.