Dover (dōˈvər) [key], town (1991 pop. 33,461), Kent, SE England, on the Strait of Dover, beneath chalk cliffs (the "White Cliffs of Dover") c.375 ft (114 m) high. The small Dour River flows through the town. Dover is a resort and an important port for travel and shipping to the Continent; it was chief among the members of the Cinque Ports. It is also a principal ferry port to Calais. Some light industry has developed in Dover. The Romans fortified the place and called it Dubris. In Anglo-Saxon times a fort was built there. In 1216, Dover was defended by Hubert de Burgh against a French attack. In the English civil war it was taken (1642) by the parliamentarians. It was the landing place of Charles II in 1660. Only 21 mi (34 km) from France, Dover was the center of English Channel defense and an important naval base in World War I. It was a constant target of German long-range guns for four years in World War II. In the cliffs a series of subterranean caves and tunnels once used by smugglers were put to use as shelters from 1940 to 1944. Improvement of the extensive harbor occurred in the late 19th and early 20th cent. Noteworthy are Shakespeare Cliff (the first coal in Kent was discovered there in 1822); the 13th-century Maison Dieu Hall, hostel of Hubert de Burgh; Dover Castle on the cliffs, of Roman or Saxon origin; the lighthouse in the castle, partly Roman; the Church of St. Mary, also in the castle, of Saxon origin with Roman brick; the barracks; and St. Martin's priory (1332), part of Dover College, a boys' school.