East London is the northeastern part of Greater London, England, east of the ancient City of London and north of the River Thames as it begins to widen. Containing areas in the historic counties of Middlesex and Essex, East London developed as London's docklands and the primary industrial centre. The expansion of railways in the 19th century encouraged the eastward expansion of the East End of London and a proliferation of new suburbs. The industrial lands of East London are today an area of regeneration, which are well advanced in places such as Canary Wharf and ongoing elsewhere.