The Strait of Dover or Dover Strait, historically known as the Dover Narrows is the strait at the narrowest part of the English Channel, marking the boundary between the Channel and North Sea, separating Great Britain from continental Europe. The shortest distance across the strait is from the South Foreland, 33.1 kilometres (20.6 miles) northeast of Dover in the county of Kent, England, to Cap Gris Nez, a cape near to Calais in the French département of Pas-de-Calais, France. Between these points lies the most popular route for cross-channel swimmers.

The White Cliffs of Dover are cliffs that form part of the English coastline facing the Strait of Dover and France.

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