Only an estimated 15,000 fans braved the poor weather to watch Saturday's qualifiers - a figure well down on last year's attendance of 60,000.
Traffic jams stretching up to 15 miles lined the roads to Silverstone race circuit, in Northamptonshire.
Queues were said at one point to be growing at a pace of one mile a minute, reaching back to the M40 and the M1 motorways.
Silverstone officials had been confident of avoiding the traffic turmoil of Saturday's race qualifiers, when the closure of water-logged car parks caused congestion outside the circuit.
The decision to run the race in earlier than usual in the year has been blamed by many for the problems, with poor weather and Easter holiday traffic combining to spoil many fans' plans.
Some decided to get out and walk, leaving their cars at a nearby motorway service station.
Brian Shearsmith, 36, who set off from Hull at 7am with his brother, said "I'm not paying £160 and not seeing the race.
"They should have cancelled the race if people couldn't get there."
Colin Maguire, 35, from North Shields also walked with his four relatives after being stuck for two hours on the A43.
He said: "The race is too early in the year. It was lovely and sunny last year and that makes the whole event."
High hopes
British hopes are high on the track after rookie English driver Jensen Button qualified his Williams in an excellent sixth position, two places behind the McLaren of Scotland's David Coulthard.
Brazilian Rubens Barichello is on pole position for the big race in his Ferrari. Michael Schumacher is in fifth, with Britons Eddie Irvine 9th and Johnny Herbert 14th.
Only an estimated 15,000 fans braved the poor weather to watch Saturday's qualifiers - a figure well down on last year's attendance of 60,000.
Repair work had continued throughout the night to ensure that car parks could cope with the 40,000 cars and 90,000 people expected to attend Sunday's Grand Prix.
Silverstone spokesman Peter Morris said the circuit had been concerned about the possibility of poor weather after the sport's governing body the FIA decided to switch this year's British Grand Prix from July to April.
The move will cost Silverstone an estimated £3 million in lost revenue afters organisers' worst weather fears were realised.
Morris insisted that the weather and the date of the race were out of Silverstone's control, but added that the Grand Prix could be moved back to its traditional July spot next year.
Date change
"We expressed our concerns to the FIA when the date was changed," he said.
"The date for 2000 has stayed but we've had permission from them to start marketing the 2001 British Grand Prix on a July date.
"We would be very hopeful that it could revert to July."
He said Silverstone had prepared for bad weather by placing around 300 tonnes of "hardcore material" on major entrance routes, and another 300 tonnes was being used in car parks to prevent further damage to the grass.