Motorway that doesn't exist

This is Motorway M96 but it doesn't really exist. It is a short strech built on runway at the former RAF Moreton-in-Marsh now used by Fire Service Training College. It is used to teach firefighters in training how to deal with road traffic accidents. The BBC used the location to film the docudrama The Day Britain Stopped about a series of catastrophic transport accidents. For the purposes of the program, the motorway was temporarily rebranded "M91".