I am never attempting to go to a large event organised south of Bath again. I knew the roads were shit, but to be stuck just south of the M4, spent an hour going about 2 miles with 25-odd miles of the journey to go, no sign of a reprieve and just one hour before the show started, is frankly diabolical. We turned round and went home again.
I will try to claim the £35 ticket money back from the organisers, as I suspect over half the people will miss the majority if not all the show. Never mind the wasted fuel.
Oh, for anyone coming to the party, avoid the M4/M5 towards Chippenham/Bath/Bristol.