Gründjitobel Viaduct, arch bridge

The Gründjitobel Viaduct is a reinforced concrete railway bridge in Langwies that spans a deep, eroded gorge with a single large arch about 86 meters long. The structure measures approximately 145 meters in length and stands about 46 meters above the valley floor, allowing trains to cross without numerous supports beneath it.

The Chur–Arosa line was built privately between 1912 and 1914, requiring 18 tunnels and 40 bridges through the difficult Schanfigg terrain. At the Gründjitobel, engineers replaced a multi-pier design with a single reinforced concrete arch to avoid piers being undermined by the gorge stream. The falsework by Richard Coray of Trin was erected from 10 July to 26 August 1913, the main arch was concreted by 15 September 1913, and the viaduct was finished on 1 July 1914.

The gorge below the viaduct is a gravel moraine cut by erosion, and its sandy formations are known locally as "Steimannli". The line it carries links Chur with Arosa, a holiday and recreation resort, so passengers cross the Gründjitobel on a metre-gauge train. The bridge is now owned and operated by the Rhaetian Railway.

The viaduct stands between Peist and Langwies, at the spot called Matten-Gründji, on the metre-gauge Chur–Arosa line; trains cross it in seconds, so watch for the arch on the approach. The gorge below is cut into gravel moraine and shows sandy erosion forms known as "Steimannli". Paths in the area let you look up at the 85-metre arch from the valley side.

The falsework for the main arch came from Richard Coray of Trin and had already served on the Halen Bridge near Bern. It was erected between 10 July and 26 August 1913, and the arch was concreted by 15 September; the whole viaduct was finished on 1 July 1914.