The Gotthard Base Tunnel, a 57-kilometre railway tunnel beneath the Swiss Alps, marks its 10th anniversary this month. It is the longest and deepest transport tunnel in the world, with trains passing 7,546 feet below the surface at its lowest point. The tunnel cost approximately £11.2 billion (CHF 12.2 billion) and took 17 years to build.
Construction and Engineering Feats
Construction began in 1999 and concluded in 2016. Workers removed over 28 million tonnes of rock using tunnel boring machines and precision blasting. The tunnel is a base tunnel, meaning it runs through the mountain's base rather than over the peaks, allowing for a straight and level route. This design enables high-speed trains to travel at up to 250 km/h, significantly reducing journey times between northern and southern Europe.
Operational Impact and Traffic Growth
Since its opening in June 2016, the tunnel has transformed rail travel between Rotterdam in the Netherlands and Genoa in Italy. The journey from Erstfeld in the north to Bodio in the south takes just 20 minutes. According to Swiss Federal Railways, the average daily passenger traffic through the tunnel nearly doubled from 9,000 in 2015 to 16,400 in 2025. Prior to the tunnel's construction, trains had to navigate winding mountain routes, limiting speed and freight capacity.
