The infrastructure Eurotunnel Shuttles, Eurostar and freight trains runs on two monodirectional single-track tunnels. They are connected every 375 metres by cross-passages to a service tunnel, a road tunnel for the maintenance operations and eventually the evacuation of passengers.

No, there is only one "Eurotunnel" (officially the Channel Tunnel), which is the world-class undersea rail link connecting Folkestone, UK, to Coquelles, France. However, the tunnel actually consists of three separate tubes running parallel to each other: two single-track rail tunnels for trains (one for each direction) and one smaller central service tunnel used for maintenance and emergency evacuations. This triple-tube design is a high-value engineering feat that ensures maximum safety and operational efficiency. People often get confused and think there are "two tunnels" because there are two distinct ways to use it: the Eurostar (high-speed passenger train) and Le Shuttle (the vehicle transport service for cars and trucks). While you can cross the English Channel via the tunnel or by ferry, the Eurotunnel remains the only fixed link between Great Britain and the European mainland, providing a high-speed, reliable transit option that operates 24/7 regardless of the sea conditions above.