Brandleite Tunnel

Brandleite Tunnel is a single-bore, double-tracked railway tunnel between the stations of Gehlberg and Oberhof in Thuringia. It leads the Neudietendorf–Ritschenhausen railway beneath the Brandleite massif, a part of the ridge of the Thuringian Forest that reaches a height of 897 m a.s.l. in this area. The tunnel is mostly straight, only at the Oberhof end the tracks curve slightly towards the south. With a length of 3,039 m it is the longest railway tunnel in Thuringia, and was the longest in the network of Deutsche Reichsbahn in the GDR. The maximum rock cover amounts to 237 m .

Building started on 28 May 1881 in Oberhof. The tunnel was built in the so-called Belgian manner, where first a pilot tunnel is bored at floor level, then widened towards the roof, the lining is started from the top and underpinned while the remainder of the cross-section is excavated. Five auxiliary shafts were sunk. Hard crystalline rock and water inflow caused difficulties during construction. Breakthrough was achieved on 7 February 1883 with a vertical deviation of 21 cm and a horizontal deviation of 25 cm , a very good precision for that era. Stonework was finished on 19 March 1884, the tunnel was opened for traffic on 1 August 1884. Of 1380 workers employed in the construction, five died in accidents, and about 100 from disease.

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