Channel Tunnel

The Channel Tunnel provides a 50-kilometer underground rail link between France and the United Kingdom, 37 kilometers of which are under the sea. Built on behalf of Eurotunnel, the structure was drilled up to 40 meters below the seabed and comprises three parallel tunnels: two single-track rail tunnels 7.60 meters in diameter and a central service tunnel 4.80 meters in diameter, dedicated to maintenance, ventilation, and safety.

Bouygues Travaux Publics was heavily involved in digging the tunnels on the French side. Opened in 1993, the Channel Tunnel was at the time the longest undersea tunnel ever built using a tunnel boring machine.

Designed to guarantee a high level of reliability and safety, the structure incorporates extensive technical equipment: 20,000 lighting points, 800 telephones, 4 ventilation plants, 250 technical rooms, and nearly 200 kilometers of piping. The railway installations include 250 kilometers of track, 174 switches and 238 kilometers of fiber optic cables.

By operating exclusively for rail traffic, the Channel Tunnel contributes to lower-carbon cross-Channel trade and is a key infrastructure for European mobility and cooperation between regions.