RAF Alconbury began as a satellite base for nearby RAF Wyton during the early days of World War II. The first American unit at Alconbury was the 93rd Bombardment Group and its B-24 Liberators. The 93rd BG flew Eighth Air Force’s first operational B-24 mission to the continent, attacking the Lille Steelworks in Belgium.
In 1983, TR-1s (reconnaissance spy planes) were permanently based at Alconbury. This led to a large remodelling of the northern section of the airfield to accommodate these aircraft and their specialised mission.
Work included the construction of five prefabricated Ready Sheds, thirteen extra wide Hardened Aircraft Shelters, a Squadron Headquarters, a massive Avionics and Photography Interpretation Centre, and new concrete aprons and taxi ways.
The bunkers and site are now being demolished except one which is Grade II listed (Magic Mountain TR1 Facility) which is said to be the last ever bunker to be built.