Near the German border, in Westerwolde (Southeast Groningen), is the fortress Bourtange.
In 1580 William of Orange gave the order to build a fort on the sand ridge in the Bourtanger moor, on the border of modern Germany. On the order of William Louis of Nassau the fortress was raised in 1593.
Between 1593 and 1851 Bourtange was an important fortress. An agrarian village came into being when the fortress was dismantled in 1851. Only a few buildings still remembered the glory of yesteryear. In the nineteen sixties the county of Vlagtwedde took the initiative to reconstruct the fortress. The plan was implemented between 1967 and 1992. Ramparts were again raised, ditches were dug and soldiers’ barracks were built.
References: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.