The Strait of Dover is the strait at the narrowest part of the English Channel. The shortest distance across the strait is from Dover in England, to Pas-de-Calais, France. On a clear day, it is possible to see the opposite coastline and shoreline buildings with the naked eye, and the lights of land at night.
The strait is the busiest international seaway in the world, used by over 400 commercial vessels daily. (source)
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