German V1 bunker @ Eperleques, about 30 miles from where i live, just across the French border..

Translaton :
right plaque:
" People, please be humane
to the brave American and English aviators who died in these parts
An affectionate tribute by the community of Eperleques."
the left one says
"People please unite
To the Belgian political prisoners, to the forced laborers , Belgians, French, Dutch , Polish and Russian"
Can't read the rest well enough from pic to translate

That's how close the 40 prisoners stood in the railway boxcars... later on they packed 100 in there.. about 35000 forced laborours worked to build the bunker. Including some folks from my home town.
That "dent" top left, is from a Tallboy... Even those couldn't penetrate the main bunker.

the onsite Concrete mixing factory, it was bombed, killing Belgians working there, some folks from my home town are known to be buried in this pile.
It looks so much bigger in person.
That door is thicker then my car is wide...

Tallboy

V2 launcher

Bigass Tallboy fishpond