Constructed 2001-2010 Length 4043m | Opened December 2010 Grade 10.5% | |
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Line Luzern–Stans–Engelberg-Bahn Track gauge 1,000 mm (3 ft 3 ⁄8 in) | ||
The Grafenort – Engelberg Tunnel is a railway tunnel built on the Luzern–Stans–Engelberg-Bahn, part of the Zentralbahn in Switzerland.
Historically, the Luzern–Stans–Engelberg-Bahn had a very steep 25% incline between Grafenort and Engelberg; replacing this with a more direct tunnel has shortened uphill journey times by 14 minutes, and increased capacity. Thanks to timetable changes, journey times between Engelberg and Zurich/Bern have been shortened by 19 minutes.
Great care had to be taken with risk assessments and mitigation; some surrounding areas are very vulnerable to floods, landslides, or avalanches. Serious flooding in 2005 not only disrupted tunnel construction, but also trapped 1500 tourists in Engelberg, who had to be airlifted to safety.
Construction of the tunnel posed several severe technical challenges; this also increased the cost, to 176.5 million CHF. As the tunnel allows the use of longer, faster trains, a new power station has been built to provide additional electrical power.