Canary Wharf is an area of London, England, located near the Isle of Dogs in the London Borough of Tower Hamlets. Canary Wharf is defined by the Greater London Authority as being part of London's central business district, alongside Central London. With the City of London, it constitutes one of the main financial centres in the United Kingdom and the world, containing many high-rise buildings including the third-tallest in the UK, One Canada Square, which opened on 26 August 1991.Developed on the site of the former West India Docks, Canary Wharf contains around 16,000,000 sq ft (1,500,000 m2) of office and retail space. It has many open areas, including Canada Square, Cabot Square and Westferry Circus. Together with Heron Quays and Wood Wharf, it forms the Canary Wharf Estate, around 97 acres (39 ha) in area.