Gotthard Base Tunnel

A giant tunnel goes through the Alps.

It is the longest rail tunnel in the world. It is also the deepest one.

The tunnel is very flat. This helps fast trains move easily. It also helps heavy freight trains. Moving goods by train helps keep the air clean.

This tunnel is a great way to travel through the mountains.

The Gotthard Base Tunnel is a huge railway tunnel. It goes through the Alps in Switzerland.

It is the longest railway tunnel in the world. It is also the deepest one.

Most mountain tracks are very winding. They go up and down a lot. This tunnel is different because it is flat. This is called a base tunnel. It stays at a low level. This helps fast trains and heavy freight trains move easily.

Moving goods by train is better for the Earth. It helps move things from trucks to trains. This can stop road crashes and keep the air cleaner.

Building the tunnel was a big job. It cost 12.2 billion Swiss francs. The work started in 1999. Drilling was done by 2011. The tunnel opened in June 2016. It is very deep under the rock. Without air, the heat inside reaches 46 degrees Celsius. The tunnel connects the north and south of Europe. It makes trips much faster for people. It can save one hour of travel time.

The Gotthard Base Tunnel is a massive railway tunnel in Switzerland. It cuts through the heart of the Alps.

This tunnel is the longest railway tunnel on Earth. It is also the deepest traffic tunnel in the world. Most mountain tracks are winding and climb high up. This tunnel is different because it is a base tunnel. A base tunnel stays at a low level. This creates a flat path through the mountains.

This helps high-speed trains and heavy freight trains move much faster. It also helps move goods from trucks to trains. This can reduce road crashes and help the environment.

Working through the mountains is a huge task. The tunnel consists of two single-track tunnels. These connect the town of Erstfeld in Uri to Bodio in Ticino. The path goes deep below the town of Sedrun.

The tunnel passes under several different mountain ranges. These include the Glarus Alps and the Saint-Gotthard Massif. It even goes under the Surselva valley in Grisons. At its deepest point, there is a thick layer of rock above it. This rock layer is 2,450 meters thick. The tunnel is so deep that the temperature can reach 46 degrees Celsius. This happens if there is no ventilation to move the air.

People have used the Gotthard Pass for a long time. Since the 13th century, it has been a way to trade. In 1830, the first road was built over the pass. Later, in 1882, the first Gotthard Railway Tunnel opened. That old tunnel was very winding and went up and down. This made travel an adventure for the rich. In 1922, the railway was electrified to make it faster. The new base tunnel project was part of the New Railway Link through the Alps. Swiss voters approved this big project in a 1992 referendum.

Building this tunnel was a very expensive and long job. Construction started in November 1999 at a place called Amsteg.

Workers finished the drilling in March 2011. The tunnel finally opened in June 2016. Full service for trains began in December of that year.

The total cost was about 12.2 billion Swiss francs. In August 2023, a freight train derailed inside. This forced the tunnel to close for over a year. It finally reopened to travelers in September 2024.

This tunnel links the north and south of Europe. It connects the German-speaking areas to the Italian-speaking areas. One end is near the river Reuss in the north. The other end is near the river Ticino in the south.

Traveling through the tunnel saves a lot of time. It cuts the trip from Basel to Milan by one hour. It also saves 45 minutes from Lucerne to Bellinzona. The weather can feel very different at each end. The south side is often warmer than the north side. This is because the climate changes as you cross the mountains.

The Gotthard Base Tunnel (GBT) is a massive railway tunnel through the Swiss Alps. It serves as a vital link for transport across Europe. This tunnel is the longest railway tunnel in the world. It is also the deepest traffic tunnel on Earth. Unlike older mountain routes, the GBT is a "base tunnel." This means it provides a flat, low-level path through the mountains.

Most mountain railways must climb steeply. The GBT avoids these steep climbs by staying low. This allows high-speed passenger trains and heavy freight trains to move efficiently. It is a central part of the New Railway Link through the Alps (NRLA) project.

The tunnel is a large complex made of two single-track tunnels. These tubes connect Erstfeld in the canton of Uri to Bodio in the canton of Ticino. The route passes deep beneath the town of Sedrun in Grisons.

To create this path, engineers had to drill through several mountain massifs. The tunnel runs under the Glarus Alps and the Saint-Gotthard Massif. It also passes under the Surselva valley. At its deepest point, the tunnel sits under a rock layer 2,450 meters thick. Because it is so deep, the temperature can reach 46 degrees Celsius without ventilation. This heat comes from the natural temperature of the deep earth.

Geographically, the tunnel crosses several important boundaries. It passes under the Chrüzlistock crest and the Piz Vatgira summit. Near Piz Vatgira, the tunnel reaches its maximum depth. The path also crosses the main chain of the Alps. This point is the main drainage divide between the Rhine and the Po rivers. This means water on one side flows toward the North Sea, and water on the other flows toward the Mediterranean. The tunnel connects the Urner Reusstal valley to the Valle Leventina.

These valleys are separated by the massive mountain barrier of the Saint-Gotthard Massif.

History shows that the Gotthard Pass has been important since the 13th century. It has always been a short link between the Rhine and the Po rivers. For centuries, travelers used simple bridle paths. The first road was built in 1830. Later, the original Gotthard Railway Tunnel opened in 1882. That older route was a "vertex line," meaning it was very winding and steep.

In 1922, the railway was electrified to improve speed. Even with modern roads and older tunnels, the mountain barrier remained a challenge. The GBT was designed to solve these old problems by providing a direct, flat route.

The project was approved by Swiss voters in a 1992 referendum. After this, preparatory work began in 1996. Construction officially started in November 1999 at Amsteg.

Drilling operations were completed in March 2011. The tunnel opened in June 2016, and full service began in December 2016.

The total cost of the project was approximately CHF 12.2 billion. The tunnel faced a setback in August 2023 when a freight train derailed. This event forced the tunnel to close for over a year. It eventually reopened to the public in September 2024.

The GBT has massive significance for European transport and the environment. It aims to shift freight from trucks to trains. This helps reduce environmental damage and deadly road crashes on mountain highways. The tunnel also saves a lot of time for travelers. It cuts the journey between Basel/Zürich and Milan by one hour. The trip from Lucerne to Bellinzona is also 45 minutes faster. It connects the German-speaking north with the Italian-speaking south. This makes the connection between northern and southern Europe much stronger.

One interesting aspect of the tunnel is the change in climate. The Alps influence the weather at both ends of the tunnel. Architect Mario Botta noted that the light changes at the Gotthard. The Mediterranean light in the south is different from the continental light in the north. On average, the south side is about 2 degrees Celsius warmer than the north side. On some days, this temperature difference can be much higher. This shows how the mountain range acts as a massive barrier between different weather systems.