This was one of the five built the others being Reigate, Sarre, Broadwater Down, Aldershot.
Entrances to the tunnel are located behind a large house situated behind St Martins Avenue.
The tunnels were sealed off for many years up until 2007 when Underground Kent documented it. Unfortunately the tunnels were in very poor condition with only the stairs/shaft and part of the tunnel behind a gas tight door accessible. The rest is behind a collapse in the tunnel system.