The Channel Tunnel (sometimes nicknamed Chunnel) linksCoquelles, Pas-de-Calais (France) with Folkestone, Kent (UK). This rail tunnel, located beneath the Dover Strait and the English Channel, is 50.5-kilometer (31.4 miles) long. The Chunnel has second the longest undersea portion of any underwater tunnel on the planet. The lowest point of the tunnel is 75 meters (250 feet) deep. The tunnel transports about 21 million people a year.

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