Albula Tunnel

Geschichte

The Albula Tunnel is the centrepiece of the Albula Railway, which forms part of the Rhaetian Railway network, in the Canton of Graubünden, Switzerland. With its maximum elevation of 1820m above sea level, it is amongst the highest tunnels in the Alps, and has a mountain overlay of up to 950m. The tunnel has a length of 5865m.The northern portal of the tunnel is at Preda, in Bergün, and the southern portal at Spinas, in the Bever valley. At a total length of 5,865m, the tunnel connects the Albula Valley with the Engadin Valley, and, in so doing, passes under the watershed between the Rhine and the Danube a few kilometres west of the Albula Pass.The tunnel serves both passenger and freight traffic. The Glacier Express passes through it daily. Until 2011 during the Winter car transporter trains operating between Thusis and Samedan also used the tunnel.HistoryThe construction of the tunnel caused unusual problems. The cold, 6°C, water outflows transformed the already fractured rock into a pulpy mass, regularly clogging up the shell of the northern tunnel lead (or adit). At the same time, a strong water source above the northern tunnel portal dried up. The water streaming in at 300L/s had to be painstakingly diverted with pipelines. As a result, construction virtually came to a standstill: in the ten weeks from May 1900, only 2m of tunnel were driven. These difficulties could not be overcome by the head construction contractor Ronchi & Carlotti, which went into bankruptcy.