The World’s Longest Railway Tunnel Opens Under the Alps

On 1 June 2016, Switzerland formally inaugurated the Gotthard Base Tunnel beneath the Saint-Gotthard Massif, at its opening the longest and deepest railway tunnel in the world. Stretching 57 kilometres between portals at Erstfeld in the canton of Uri and Bodio in Ticino, the twin-tube tunnel took seventeen years to build after work began in 1999. It was engineered to carry trains beneath the central Alps on a low-level route rather than over them.

People and goods had crossed the Alps for centuries on foot, on horseback and later by stagecoach, car and truck, but steep gradients made the mountains difficult for railways. The first Gotthard rail tunnel, opened in 1882 as the major Swiss construction project of the late nineteenth century, ran for 15 kilometres between Göschenen and Airolo, yet its portals sat at roughly 1,100 metres above sea level and its highest point at 1,151 metres. Trains had to climb slowly toward it, in places spiralling through loop tunnels, a route poorly suited to heavy modern freight.