Hundreds of revellers have been forced to sleep in their cars after traffic became gridlocked when the Isle of Wight Festival site turned into a mudbath caused by heavy rains.
The queues caused ferry companies to suspend their services and about 600 people were stranded on Thursday night on ferries on the Solent as the boats could not be disembarked because of traffic build-up on the island.
The problems started after heavy rain fell on Thursday, water-logging the event car parks at Seaclose Park, Newport, meaning that they became churned up with mud as cars began to arrive.
This led to the car parks becoming inaccessible and long queues forming, stretching back to the port towns of Ryde and Cowes.
Police led many of those waiting to Newport Football Club where they were given shelter overnight.
Now organisers are urging anyone still waiting to get to the island to leave their cars. A festival spokeswoman said: "If you are on the mainland we are advising people not to travel by car. There is a ferry service for foot passengers and this will be the easiest route. We are sorry for any disruptions caused."
Promoter John Giddings said in an interview with BBC Radio Solent: "Believe you me, I am doing everything in my power and the police are telling me to do everything in my power, because they want an emergency plan from me by Sunday about how we are going to get people out."
Fiona Gregory, from Salehurst in East Sussex, said that she had left home at 1.30pm on Thursday and was still stuck in queues in the early hours of this morning. She told the BBC: "I'm so upset. It's a complete disaster. On the island it has been a nightmare."
More than 50,000 people are travelling to the festival which is being headlined by Pearl Jam, Tom Petty and the Heartbreakers and Bruce Springsteen and The E Street Band.
Entertainment started on Thursday night for those who had reached the site although the Big Top stage was evacuated at one stage because of heavy wind and rains although did reopen again for headliners Primal Scream. The Charlatans also played an exclusive warm-up gig at Spitbank Fort, a Napoleonic Fort in the middle of the Solent, organised by Absolute Radio.