On the way out from IJmuiden as well as the windsurfers (see previous posts) we passed a fortified island, which is named Fortress Island.

I assume the fortifications were built by the Germans during World War 2 as part of their Atlantic Wall.

Industrial IJmuiden in the background:-

A bit further on. I can’t decide if the rectangular array is a set of solar panels. I think it must be, so obviously a much later addition:-

Are the serrated things in this view tank traps?