Kernwerk

After the Noordzeekanaal (North Sea Canal) had been completed, a coastal fortress was built on its southern bank near the mouth of the canal. It was part of the Stelling van Amsterdam, the Amsterdam Defense Line. Because of subsequent excavation of a second entrance to the canal, the fortress was effectively located on an island. This “Fort Island” controlled access to the harbors, the system of locks, and the industrial areas of IJmuiden and Amsterdam. During the 1939-1940 mobilization, the Dutch built a handful of light concrete fortifications, one of which is still present on the extreme southwestern tip. The German navy turned the island into the redoubt or stronghold of Festung IJmuiden. They built a coastal battery overlooking the sea. It featured three artillery bunkers (type M170), troop bunkers (type 656) and a type 636 fire control post located on top of the old fort. Impressive stairwells connected the bunkers to the interior of the fort. An emplacement for firing depth charges prevented the passage of ships. The perimeter defense was supported by three cannon, six pieces of anti-tank artillery, and six heavy caliber machineguns, all in casemates. The island itself was defended by grenade launchers (two) and machineguns (eight), the latter located under four steel cupolas. The small beach on the west side of the island was obstructed with dragons’ teeth.

After 1945, the waterways were excavated and enlarged and about two-thirds of Forteiland was cleared in the process. All that is left today are the old fort and eleven German bunkers. Two coastal battery artillery casemates have been spared, the third one is partially demolished. One type 671 gun casemate remains, as well as one type 644 bunker for a pair of machineguns shielded by an armored gun cupola, the latter the only remaining specimen in Europe. The site includes a rare type V191 bunker from which depth charges were launched, a type 630 casemate with armor plating for anti-tank guns, two personnel bunkers (types 635 and 668) and a water storage facility. The Dutch fort and the German bunkers are open to the public.