The Channel Tunnel, also referred to as the Eurotunnel is a 50.45-kilometre railway tunnel that connects Folkestone with Coquelles beneath the English Channel at the Strait of Dover. It is the only fixed link between the island of Great Britain and the European mainland. At its lowest point, it is 75 m deep below the sea bed and 115 m below sea level. At 37.9 kilometres, the tunnel has the longest underwater section of any tunnel in the world, and is the third longest railway tunnel in the world. The speed limit for trains through the tunnel is 160 km/h. The Channel Tunnel is owned and operated by Getlink.
The tunnel carries high-speed Eurostar passenger trains, the Eurotunnel Shuttle for road vehicles and international freight trains. The tunnel connects end-to-end with the high-speed railway lines of the LGV Nord in France and High Speed 1 in England. In 2017, through rail services carried 10.3 million passengers and 1.22 million tonnes of freight, and the Shuttle carried 10.4 million passengers, 2.6 million cars, 51,000 coaches, and 1.6 million lorries. This compares with 11.7 million passengers, 2.6 million lorries and 2.2 million cars by sea through the Port of Dover.