Royal Ordnance: ROF Elstow
Elstow Storage Depot was one of sixteen UK Ministry of Supply, World War II, Filling Factories. It was a medium-sized filling factory, (Filling Factory No. 16), which filled and packed munitions. It was located south of the town of Bedford, between the villages of Elstow and Wilstead in Bedfordshire. It was bounded on the northeast by the A6 and on the west by a railway line. Hostels were built nearby to accommodate the workers who were mostly female.
It was built with the Ministry of Works acting as Agents; building work started in November 1940 and was completed by August 1941. It was managed as an "Agency Factory" by J. Lyons and Co on behalf of the Ministry of Supply as, by then, the Ministry of Supply was overstretched in regards recruiting and managing the workers needed to staff these munitions factories.
It had 250 buildings and 15 miles of standard gauge railway lines. It was linked to the Midland Railway line running between London and Bedford. The site does not appear on Ordnance Survey maps made during wartime or in the postwar period. 
Sources of Information
-  wikipedia