Denmark
WWII German coastal defences at Hanstolm
Photos from my trip to the Kingdom of Denmark in 2001.
The tourist brochure states these are Europe's largest survivng World War 2 fortifications. That may well be. I can personally attest to their largeness!
The entire west coast of Denmark was fortified against coastal assault and the entire country fitted out with AAA installations and further bunker systems set to deter parachute landings.
The museum at Hanstolm is being refurbished and they have set up a 15in gun on loan from the Danish Navy. Apparently there is a 38 incher still in situ in Norway. I'd like to see that!