This is a curious bunker site with just one remaining building but sandwiched between two large complexes.
On private property, permission must be granted to visit Stp189 Rhein where you can find a combination construction of a Vf2a personnel shelter with an additional Tobruk.
The Vf2a is of a standard design with two entrances leading to one main room and an escape shaft which still has its original steel ladder rungs and part of the brick surround on the outside.
The Tobruk isn’t a standard design though and is of a two storey design, giving it much more height for better observation. It’s accessed via stairs near inside one of the entrances to the Vf2a – now bricked up inside – but this design created a single, circular room below.
There isn’t any access to the Tobruk from this room, and no opening can be observed to have been bricked up either, so the room was likely used as a shelter or storage as it’s not large enough for troops to use as accommodation.
Stp189 Rhein is sandwiched between Stp188 Schlesien, a former Luftwaffe airfield with more than dozen remaining buildings including fighter pens and defensive bunkers, and Stp192 Bismark where you can find a large Dombunker for the K5 railway guns which operated in the Marquise area.