Theydon Bois is a London Underground station in the Epping Forest district of Essex. It is served by the Central Line and is between Debden and Epping. For the purposes of fare charging it is in Zone 6.
The station was opened as "Theydon" by the Great Eastern Railway (GER) on 24 April 1865, as an intermediate station on their Loughton-Ongar extension; the GER became part of the London and North Eastern Railway (LNER) in 1923. 'Milk trains' to Liverpool Street were a regular feature in the timetable until the underpass from Leyton to Stratford was built.
As part of the 1935-40 New Works Programme projected the extension of the Central line over this LNER route. However, the further extension of the Central line from its new eastern terminus at Loughton was not clear cut. Considerable high level discussions were held regarding the further extension to the Central line from Loughton to Epping. Eventually the presence of new housing estates, including a large London County Council estate at Debden with over 4000 housing units, swung the decision in favour of continuing and Theydon Bois opened as an intermediate station on the Central line on 25 September 1949.
The station today 
As of 5 February 2006, the station is one of the first on the network to operate without a staffed ticket office. The station is staffed 24 hours a day, 364 days of the year.
Looking north ('eastbound') towards Epping
Looking south ('westbound') towards London
Looking north from public footbridge