Lager Koralle Bunker Ruins

Impressive when suddenly the ruin of the old bunker in front of you rises from the forest in front of you.

Actually, the high bunker ruin "Lager Koralle" consists of two bunkers, which are about 200 m apart: the high bunker type T 750 (troop crew bunker for 750 people) and the anti-aircraft bunker (also situation room bunker). In the situation room bunker, the situation conference room and the office of the BdU were on the upper floor, and the operating rooms for the intelligence staff were on the lower floor. On the roof were three anti-aircraft positions for anti-aircraft guns (hence the anti-aircraft bunker).
There are a number of very nice pictures and actually all of the Komoot'ler have actually limited themselves to the essentials - i.e. to the highlight itself. I've seen it differently too.

Wikipedia:
The object was first intended as a marine communications school and received the name "coral" later. Construction began in 1939 in a heavily wooded area two kilometers northwest of Lobetal, north of Bernau. The site originally belonged to the Hoffnungstaler Anstalten.
Due to the increasing danger of aerial bombs it was decided to relocate the command center of the Oberkommando of the Kriegsmarine (OKM) from Berlin to a safer area. On January 30, 1943, it moved into the camp Koralle. A little later, the main radio station of the commander of submarines (BdU) was set up locally. All the communication links for the submarine warfare were now sent to the station's bombproof message bunker.
After the advance of the Red Army and encirclement of Berlin on April 19, 1945, the order was issued for the transfer to the alternative accommodation property Trout near Plön and eight days later to Flensburg-Mürwik.
After the war, much of the facility was blown up by Soviet troops. The ruins are still in place.
The Tiefbunker and Dönitz 'residential building are preserved to this day.