Just in case it is of interest, my Grandpa was stationed at Rügenwalde, Todays Darlowo
on the Railway Artillery proving grounds. That was a setup of railway lines, Tunnels (for Storage, concealed).
Eperviers Diesel Loko and Railway Gun fit perefctly. They had a mixed inventory of Railway Guns,
too much to list. Grandpa had pictures of the large Railway gun's 4 track ground, these Diesel Lokos towing a
Gun out of the Beach Tunnel and these circular Gun plattforms. He could name all the Guns, langer kurzer Bruno , Karl, heck I can't remember.
What Kaliber. From what I remember they prepped these Guns for Firing with drills for days to come.
Some barrels broke, replacement took long time, other times ripped eardrums, broken, bent tracks from the recoil, backblast.
They had a firing range that spanned an area from Rügenwalde up to Swinemünde,
over water, a restricted area. Nearby was a small Landing strip, a Detachment of Bordflieger and other Sea Planes
guarded the military zone. Grandpa said nearby were several Navy Bases, where U-Boats were
frequently seen, along with these Helis. These Bordflieger in their Sea Planes also helped in the aiming, range finding
and target verification. They had to coordinate everything with the Navy, excersises, joint were comon.
The adjacent Seeflieger Horst was amongst others Nest, north of Koszalin. more I can't remember.