Dartford is a principal town and borough in southeast London in the greater London area within the county of kent. Although it is known today as a commuter town, Dartford historically is a place of great industrial importance that dwindled in the 20th century due to the decline of its manufacturing and cement making industries. It is now known as being the home of the Blue Water shopping centre (formerly a major cement works) which has taken over from the high street as being the boroughs commercial centre, although many discount chain stores and supermarkets still occupy the old shopping district along the B2500.