You're probably thinking about the Thames Barrier which is located to the east of London and not in Central London. It is a structure which lies on the bed of the River Thames which can be raised when a particularly high tide is predicted to protect Central London from flooding.
London Bariier
Yes it is located in central London.
Heathrow Airport is located about 20 miles west of central London and Gatwick Airport is located about 30 miles south of central London. Both airports have excellent transport connections to central London.
The King's Cross railway station is located in London. It is a major London railway terminus, specifically located on the northern edge of central London.
Greenwich is a suburb of southeast London about 10 miles from central London.
On Silvertown Way in east London - about5 miles from central London.
London Borough of Islington, about 4 miles northeast of central London.
Belgravia is an area of central London, located in the City of Westminster.
The cheap hotels located in London Central are the City Hotel of Westminster, London Hotel, Hotel of Saint James, City Inn of Westminster and as well as United Hotel.
The London Dungeon is located next to London Bridge station, in central London.
"The Grand Central Railway Company is located in Britain, and the main routes are London King's Cross - Sunderland and London King's Cross - Bradford."
It is located very close to London Heathrow airport. The hotel is located in Greater London, and there are good connections you can make to get to central London from the airport.