Stellwerk Olympia-Stadion

The second opportunity i took on the Open Memorial Day was a visit of the Underground Museum¹. The Underground museum has been housed in the former signal box of the Olympic Stadium Station since 1997, hence the name “Olympic signal box”. The heart of the museum is the 14-meter-long lever mechanism of the electromechanical signal box of the VES 1913 type². VES stands for “Vereinigte Eisenbahnsignalwerke”. Commissioned in 1931 as the largest signal box of this type in Europe, the entire operation of the Betriebswerkstatt Grunewald and the Olympia-Stadion station was monitored from here. 103 points and 99 signals were set with the levers and enabled train movements with over 616 travel options. Each lever in the interlocking system controlled either a track switch (“Weiche”) or a signal, and the mechanical interlocking ensured that conflicting train routes could not be set, greatly reducing the risk of accidents. The single-row signal box was in operation from 1931 to 1983.

In the next room you can see one of the clock cabinets which formerly stood in “clock centers”. These buildings ensured that all station clocks “ran” at the same time. Synchronized timekeeping is crucial for railway operations, as precise timing is needed for train scheduling and safety. The central clock cabinets sent electrical impulses to slave clocks at each station, ensuring uniform time across the network. This system, known as a “Mutteruhr” (master clock) and “Nebenuhren” (slave clocks), was widely used in German railways and public buildings. The BVG operated in this form on Trebbiner Strasse until 1970. From the large clock cabinets, impulses went out every 30 seconds, which controlled the station clocks, which were not equipped with a clockwork³

The museum offers a rare glimpse into the technical history of Berlin’s railways, but its small rooms and dense displays can make it feel more like a Wunderkammer - a cabinet of curiosities - than a conventional museum. Without prior knowledge, some exhibits may be hard to access or interpret. Hopefully, in the future, the museum will expand its space and provide more explanatory material for visitors.