The Staircase Between Vor -and Tiefbunker

To connect the Tiefbunker and the Vorbunker with each other, the western basement corridor of the reception hall located adjacent to the Vorbunker had to be integrated into the bunker’s staircase. However, the whole western façade of the reception hall rested on a wall-like foundation, through which the new opening to the new underground corridor had to be inserted. If the reception hall was to remain intact, this section of the façade had to be artificially supported during the excavation of the passage.