Coastal Artillery is a very big deal IMHO. I'm making no pretence to cover the subject all over. Only few locations of Baltic sea coast are presented on these pages.
Finnish 12" battery in artillery museum.
Coastal artillery command point in Suomenlinna.
Finnish 12" guns and Russian battery.
Eat War battery ans Coastal Artillery School.
USA 234 mm guns and famous beacon.
Old Russian 12" battery and etc.
Finnish 6" Canet battery and mine depot.
16 inch and 12 inch guns.
Remains of Finnish 12" battery.
Ruins of Finnish 6" Canet battery.
Some Finnish and Soviet WW2 batteries.
Famous Saarenpa battery and other WW2 wreckage.
Finnish 6" emplacements and Sofiet firepost.
Soviet 152/57 mm system of 1950-th.
38 sm German gun at Skaggerak strait coast.
75 mm coastal battery in Stockholm Archipelago
Coastal 75 mm battery
Coastal 120 and 152 mm turret guns