the first three guns were situated at the hel fortified area, poland as battery schleswig-holstein during 1940 to protect the bay of danzig. all three guns were fired during may and june 1941 and shortly after the guns were dismounted and transported to france for use as battery lindemann. from this new location near sangatte in france, they were used to fire at dover, in the county of kent in england and shipping in the english channel. there is a museum of coastal defence located in the remains of the battery in hel.