Well, it's almost true...
There used to be 2 grass aerodromes; these were Wittering and nearby Collyweston. In 1943 it was decided to join the two together; this required some tree-felling and ditch filling, but ultimately provided a 3 mile grass runway. This stretched from the Great North Road all the way to Collyweston village.
It was used in the war to recover 'lame ducks' - and by trials organistaions after the war. I think the infamous Me163 conducted various (unpowered!) skid landing trials at the time.
The 9000 ft 'V-bomber' runway was built over the 3-mile grass runway in the 1950s.
As for Collyweston, well that's where we went for certain 'Special Weapons' courses. Imagine the joy of listening to a Chief Technician explaining the Pauli Exclusion Principle to you at 0830 when you've got a thumping hangover.....