Zug der RhB auf dem Kreisviadukt Brusio

Zug der Rhätischen Bahn auf dem Kreisviadukt in Brusio. Bernina Railway, today Rhaetian Railway A spiral viaduct was required immediately south of Brusio to limit the railway’s grade to the required maximum of 7%, so the train would not slip on the way up, or be uncontrollable on the way down. The spiral viaduct is 110 metres (360 ft) long, has a horizontal radius of curvature of 70 metres (230 ft), a longitudinal slope of 7%, and is made up of nine spans, each 10 metres (33 ft) in length Viadotto elicoidal