I assume you refer to Ongar, which was closed in 1994. It was situated on the Central line, east of Epping (further from central London).
Either Heathrow Terminal 5,Amersham,Morden or Upminster.They all might be the same.
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.
Central Line
The London bombing did occur in central London. The attack targeted the London Underground.
Use the tube (underground) from any terminal.
The Central line is the current oldest tube stock in the whole of the London Underground.
There is a tube (underground) station at the terminal which will take you into Central London.
The Central line only.
London Marleybone is the only terminus where only diesel trains terminate.
Central, Circle, District, Metropolitan, Waterloo.
There is a tube (underground) station at the terminal which will take you into Central London.
Take the Piccadilly Line underground (tube) train or a taxi.
Paddington.