Walthamstow is the largest district of the London Borough of Waltham Forest in east London. It is located 7.5 miles (12.1 km) northeast from Charing Cross. Historically in the county of Essex, it significantly increased in population as part of the suburban growth of London and was incorporated as the Municipal Borough of Walthamstow in 1929 before becoming part of Greater London in 1965. Walthamstow is situated between the North Circular Road to the north, the Lea Valley and Walthamstow Reservoirs to the west, and Epping Forest to the east.