The second Carfest event kicks off tomorrow (8 September) at Cholmondeley Castle in Cheshire, following the first festival at Laverstoke Park Farm in Hampshire in August.
Evans announced his idea on the radio before plans were finalised, and agency Brand Events then had to listen in to discover the plans as they evolved, even setting up a call desk in its office to deal with the number of Evans's listeners who wanted to be involved in the events.
Well known as a pertrolhead, Evans had been interested in starting his own car festival for several years.
When he had a drink with Brand Events managing director Chris Hughes in November 2011, Carfest was born. "Although we've since added lots of bells and whistles to it, he very clearly described the idea we have now," said Hughes. "A day for the family with lovely cars, good food and a party in the evening."
Discussions continued for several months but with few concrete plans being made, until Hughes received some unexpected news one morning in February 2012.
"I was driving into work and someone rang me and said 'Are you listening to this? Chris Evans is announcing the show on the radio'," said Hughes.
Hughes and his team then listened to Evans's radio show each morning as the presenter dreamt up ideas for the event, in front of a live audience of millions.
Hughes told Event: "The ideas were created on-air and we were off each day making them come true. We listened to the radio each day to discover what our jobs were.
"One morning, Evans made half an hour's radio out of discussing whether there were going to be enough chemical toilets in Britain because of the Olympics. So rather than getting involved in booking bands, we told our operations people to get on the phone and book the chemical toilets."
He added: "Lots of Chris's listeners essentially put the event on with us because they brought their food, exhibits or cars. We had to set up a call desk in our office to deal with the hundreds of members of the public ringing in with suggestions. We probably had more than a thousand. It was a collective creative act with Evans as the ringmaster."
What do you think of the way Carfest was created? Comment below and let us know.
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