Admiral Dönitz was appointed Commander-in-Chief of the Kriegsmarine.  The Koralle was his  headquarters  in the forest north of Bernau, close to Berlin. The complex consisted of two bunkers aboveground, one underground bunker (two storeys deep) and an officers-casino. One of the aboveground bunkers had a AA position on the roof, to protect the complex. The second aboveground bunker was presumebly a personnel bunker or an air-raid shelter. Dönitz's headquarters was in the underground bunker. When on April 21st, 1945 the Red Army was nearing Berlin, the OKM was transfered to Sleeswijk-Holstein. The Wehrmacht demolished Koralle. Only the officers-casino was not damaged. There is little left of this building. Originally built as a three story "L" shaped bunker. This was the main communications bunker with four giant radio antennas located on the northeast corner. Along with the 3 above ground stories, there are also three underground levels. The Russians leveled most of the structure when they abandoned the site.  a dozen dugouts surrounding the building in which the Russians parked tanks in during their stay