Anyone planning to drive to Newark up the A1 or A14 past Peterborough and Oundle should SERIOUSLY consider an alternative route... or allow a generous amount of time for the journey!
When I drove past last year the show had finished the day before - lanes coned off, drivers routed all over the place - we're talking about 135,000 visitors in the 4 days.
See the following site for maps:
http://www.eastofengland.org.uk/Showground/
As an example, last week was the smaller Suffolk Show just outside Ipswich. The town grid-locked and the A14 and part of the A12 was jammed for miles.
Deep joy....
David