There are dozens of small strongpoints located along the dunes between Calais and Dunkirk and many were built rapidly following the occupation of France in early 1940.
They each offer a first line of defence of the long, wide beaches between the larger gun batteries built later and located inland of the coast and can give you an insight into the early types of bunkers the German’s built to protect their new lands.
Stp Nikolaus, to the east of Waldham at Les Hemmes D’Oye is a classic example. This site relied on pillboxes and Vf3 machine gun positions as the main armament although a R612 casemate for a 7.5cm field gun was also added to the site on the beach front.
Except for the beach front bunkers, most are overgrown in the dunes behind but still accessible.