town and borough (district), administrative and historic county of Kent, England. It lies along the south bank of the River Thames, just east of and adjoining the metropolitan area of Greater London. In ancient times it was a marketing centre. The fording of the River Darent by the London-Canterbury road gave Dartford its name. Because of its location on the main route between London and the mainland of Europe, Dartford has been associated with many events in British history. Isabella, sister of Henry III, was married by proxy there to the Holy Roman emperor Frederick II in 1235. Henry VIII, his wife Anne of Cleves, and Elizabeth I all had private residences in Dartford. During the 16th century, some of the first English experiments in papermaking (paper) were made in Dartford. This industry is still important in the district, as are local chalk-quarrying and cement works. Industry and residential development are concentrated around the town in the north; the south of the borough, near the North Downs, is still comparatively rural. Area 28 square miles (73 square km). Pop. (2001) town, 56,818; borough, 85,911.