Eurostar locomotive and a section of the Channel Tunnel.
 The Channel Tunnel is a 50.5 km (31.4 mile) rail tunnel
beneath the English Channel and has the longest undersea
portion of any tunnel in the world.  The tunnel carries
high-speed Eurostar passenger trains, the Eurotunnel
Shuttle for road vehicles (the largest such transport in
the world) and international freight trains.  Construction
began in 1988 and it opened in 1994 at a cost
of £4.65 billion.

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