(IJmeer approx.), Located to the north of Muiden in the IJsselmeer, is an elliptical island, constructed in 1887-'95 on a shoal of the same name to protect Amsterdam from gun fire from warships. The main building (escarpne building) consists of a single-storey building with accommodation and ammunition spaces and two large gun towers.
In it were huge, liftable steel armored domes with guns (drained in World War II). Around the main building there is a wide dry moat and on the outside the contrescarp, all around with a protection of glacis and dumping stone dam. This fort, which was decommissioned after 1932, was formally lifted in 1952.
