Roads could be gridlocked this bank holiday weekend, with 52% of people planning a trip, it was revealed today.
Friday is set to be the busiest day, with 25% taking the day off and many others leaving work early, a poll by car insurance company esure found.
A total of 41% of 18 to 25-year-olds are planning a day trip over the weekend, with many lured by music festivals including the Reading Festival in Berkshire and the Leeds Festival at Branham Park in Wetherby, West Yorkshire.
Despite an unpromising weather forecast, the esure poll found plenty of people prepared to visit beach resorts, with the Isle of Wight, Blackpool and Brighton the most popular spots.
Esure said it estimated that motorists will face average delays of one hour 24 minutes, with 12% possibly experiencing jams lasting more than three hours.
The poll showed that 30% of those planning trips intended to get up early on Saturday to begin their journeys, while 33% will use minor roads and 19% will avoid motorways completely.
In all, 19% of people are planning a journey of more than four hours over the weekend.
Mike Pickard, head of risk and underwriting at esure car insurance, said: "Travel delays are standard fare for any bank holiday weekend but this week we're facing a perfect storm for delays on the road.
"Millions will opt for the car and a large percentage will not prepare properly."
The Highways Agency said around 70,000 fans would be attending the three-day Leeds Festival, while about 40,000 would be travelling to the Creamfields festival near Runcorn in Cheshire.
A spokesman for the agency said: These events bring extra traffic into the region and drivers are advised to plan extra time for their journey, take regular breaks and have drinking water with them. Drivers should also ensure their vehicles are prepared for the journey, with plenty of coolant and fuel.
"Drivers are advised to leave plenty of time to travel to the music festivals and we are working with the festival organisers, the police and local authorities to minimise delays on the roads."
Those preferring rail to road will have to contend with a number of engineering works over the weekend which will mean closure of sections of lines and the use of replacement buses.
Engineering work between Wolverhampton and Stafford will affect services run by the Arriva Trains Wales, CrossCountry, London Midlands and Virgin train companies, with buses replacing trains on some sections of the West Coast Main Line.
Other train companies affected by engineering work include First Capital Connect where work will be going on between New Barnet and Welwyn Garden City in Hertfordshire.
Buses will also be replacing trains on South West Trains' services between Ascot in Berkshire and Aldershot in Hampshire.
Tube travellers also face disrupted journeys, with upgrade work causing the entire shutdown of the Underground's Victoria line on Saturday and Sunday.
There will also be no services on the Jubilee line on bank holiday Monday and a part-closure of the line on Sunday.
This will mean cricket fans travelling to the fourth and fifth days of the England-Pakistan Test match at Lord's will not be able to use St John's Wood, the nearest station to the ground.
The AA predicted 16 million cars were likely to be on the road over the bank holiday weekend, with congestion building up from around mid-afternoon on Friday on popular routes.
But the AA added that with many schools in England not going back until the week beginning September 6, the more staggered return would take the edge off the traffic which was not expected to be as bad as in previous years.
Hotspots were expected to be:
* The M25, M1, M11, M3 and M4 around the London area;
* The M6 in the Midlands and north west England;
* The M1 in the East Midlands and the A1 northbound towards Yorkshire;
* The "usual" holiday routes - the M5, A30 and A303 to the West Country; the M3, M27 and A31 to the Dorset coast; the A11 and A47 to East Anglia; the M4 into South Wales, the M6 to Blackpool and the Lake District and the A64 to the Yorkshire coast.
Paul Leather, AA patrol of the year, said: "Although we're not expecting it to be quite as bad this year, the August bank holiday is still one of the busiest weekends in the year for travel.
"Unsettled weather makes the traffic more unpredictable, so people should check the weather and traffic reports before departing. However, come rain or shine, make sure you're prepared for the journey, as you never know when you might hit traffic on a bank holiday."
The Press Association's weather company MeteoGroup today forecast that on Thursday, Scotland and Northern Ireland would have sunny spells and scattered showers and west Wales and south-west England would be largely dry with sunny spells developing.
Elsewhere on Thursday, rain will clear eastwards to leave a generally dry afternoon with brightening skies.
Friday is expected to be bright with sunny spells and just a scattering of showers, these mainly falling across Scotland, Northern Ireland Wales and north-west England.
Network Rail (NR) and the Association of Train Operating Companies (Atoc) said there would be almost 30% fewer rail replacement bus services needed than in the August bank holiday 2009 period.
Atoc chief executive Michael Roberts said: "The vast majority of people travelling by train should experience no disruption whatsoever because of improvement work this weekend and even fewer will have to get on to a replacement bus."
NR operations and customer service director Robin Gisby said: "Passengers tell us that they would rather take another train or stay on one for longer than get on a bus, so we've listened and there will be significantly fewer replacement buses than this time last year."
Travel booking website Expedia.co.uk said domestic bookings for the bank holiday weekend had increased by more than 30% compared with the August bank holiday last year.
London and south west England were the most popular spots this summer, followed by Edinburgh.
* Supermarket chain Asda said that from tomorrow it was reducing its fuel prices by 1p a litre. This will mean drivers at the company's 180 filling stations paying no more than 110.9p a litre for petrol and no more than 113.9p for diesel.