The Bunker can be visited
Lager Koralle (OKM)

North of Bernau bei Berlin lies the former "Lager Koralle," a military facility that served as the command center for the High Command of the Navy (OKM) between 1943 and 1945. Originally conceived as a naval intelligence school, it became a strategically important location for warfare due to the threat of bombing in Berlin.
History+
Construction work for Lager Koralle began in 1939 in a densely forested area northwest of Lobetal. The site, which once belonged to the Hoffnungstaler Institutions, was later renamed. On January 30, 1943, the High Command of the Navy relocated its headquarters from Berlin to this site. Shortly thereafter, the main radio station of the Commander of U-boats (BdU) was also established at the facility, making Lager Koralle a central hub for U-boat warfare.
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Location: 52.7389, 13.5742