RAF Northolt Sector Ops Room
The RAF Northolt Sector Ops Room was built around 1928 as the prototype Sector Ops Room for the RAF. It was the building which was used (along with HQ Fighter Cmd and HQ 11Gp) to develop the whole air defence system used in the BoB. However, by the start of the war the building was not used and they had moved to the hardened building just behind and then later out to dispersed locations in Ruislip during the BoB itself.