This site, to the south of Equihen Plage, has a mix of explorable concrete constructions you can visit and the shifting sands they're stood on has meant you can get some interesting views too.
The two largest builds here are a R612 casemate and a R502 double group shelter and both have slipped form the high dunes onto the beach and now rest at a sharp angle which exposes their undersides. This allows you to take a look at the foundations that were used for huge constructions like this and there are all sorts of materials in the mix!

The R612 was build for a 7.5cm field cannon and faces to the north where it has a large expanse of sandy beach in front of its embrasure. Lying on the beach are a number of other buildings including an open emplacement for a 5cm KwK anti-tank gun and a simple MG position. Although this MG post looks as if it was in the line of fire of the R612 casemate, it wasn't originally. There are also two Tobruks on the beach and coupled with the two in the dunes behind provided a defensive ring around the site.

To the south there are the tops of two concrete tetrahedron beach defences visible and the shifting sands - it's always windy here - can expose or cover them depending on the direction of the wind.