Wanderlust World Wanderlust World The Channel Tunnel—affectionately dubbed "the Chunnel"—represents one of modern engineering's greatest achievements. This 50.45-kilometer (31.35-mile) undersea rail tunnel connects Folkestone, Kent, in the United Kingdom with Coquelles, Pas-de-Calais, near Calais in northern France. The tunnel's underwater portion spans 37.9 kilometers (23.5 miles) beneath the English Channel at the Strait of Dover, making it the world's longest undersea tunnel.
Opened in 1994 after six years of construction, the Chunnel comprises three parallel tunnels: two rail tunnels (7.6 meters diameter) for passenger and freight trains, and a smaller service tunnel (4.8 meters) for maintenance and emergency access. Eurostar high-speed trains traverse the tunnel in approximately 35 minutes, reaching speeds of 160 km/h (100 mph) underwater.
The Strait of Dover, the Channel's narrowest point, was strategically chosen to minimize underwater distance. The tunnel burrows through the chalk marl layer—a stable geological formation ideal for tunneling—averaging 45 meters below the seabed. This engineering marvel carries over 10 million passengers and 1.6 million trucks annually via shuttle services, fundamentally transforming cross-Channel travel and trade between the UK and continental Europe.