Travellers face disruption on the railways and jams on the roads during Easter.
Once Easter is over, there could be serious delays at ports when strict new passport exit checks for departing passengers are introduced on April 8.
As is usual during bank holiday periods, there is a large programme of engineering work on the railways with a number of major routes affected. WORDS: PA.
One of the most-disrupted routes is the London to Scotland West Coast main line.
Major work at Watford in Hertfordshire means that there will be no Virgin or London Midland trains able to run in and out of London's Euston station between Good Friday and Easter Monday.
Virgin trains will run no further south than Milton Keynes, Rugby or Northampton while there will be no direct London Midland services between Euston and Hemel Hempstead in Hertfordshire.
In addition, there will be improvement work on the West Coast line between Crewe and Warrington and between Carlisle and Glasgow which will severely restrict Virgin services to northern England and Scotland.
Virgin is "strongly recommending" that passengers do not travel between Good Friday and Easter Monday.
Another area in which work is going on over Easter is between Manchester and Bolton, via Farnworth.
Manchester Victoria station will be closed from Good Friday to the end of Easter Monday.
The Easter holiday will also see no Southeastern train company services running to or from the London stations of Charing Cross, Waterloo East or Cannon Street.
Other disrupted areas due to engineering work include parts of Kent, lines running through Reading in Berkshire and some services from Paddington.
The pressure will be on NR to ensure its big engineering programme finishes on time. Last Christmas there was travel chaos in north London after work at King's Cross and at Paddington stations overran.
RMT general secretary Mick Cash said: "The real problem we face is a massive backlog on the rail maintenance and renewals side which leaves engineers trying to squeeze impossible targets into limited windows of opportunity.
"That problem has been compounded by cash-led cuts to staffing and schedules which RMT has warned repeatedly would leave services on a knife edge."
On the roads, traffic information company Inrix is predicting that the worst-affected congestion hotspots in south east and south west England could be twice as busy as last Easter.
The company reckons those heading by road to Gatwick and Heathrow airports on Thursday could face up to four times the standard journey time, with a typical 30-minute journey around the western section of the M25 taking up to two hours.
Inrix said the busiest days will be Thursday, Good Friday and Easter Monday.
Inrix traffic analyst Greg Hallsworth said: "On the one hand, increased traffic on the roads, railways and public transport signifies good news for the economy, with more people travelling and increasing numbers of goods being moved across the country.
"For those planning an Easter weekend getaway, our advice is to check before you travel.
"With rail closures, diversions and huge numbers of vehicles on the roads, many routes will be busier than usual."
The RAC said that as many as 16 million motorists were set to take to the roads over Easter.
It estimated that four million will be travelling on Good Friday and around 4.5 million will be on the road on Easter Sunday.
"The first spring bank holiday of the year traditionally heralds the start of busier weekends on the nation's roads," said RAC head of external affairs Pete Williams.
He went on: "This Easter is set to be a hectic one with 16 million of us getting behind the wheel for an Easter break, but at least we will benefit from the longer days and lighter evenings to complete our journeys."
The Highways Agency, which becomes Highways England on April 1, said more than 550 miles of roadworks will be lifted over Easter on England's motorways and major A roads.
The agency aims to complete or lift 209 sets of roadworks by Thursday, with the suspended works' restrictions lifted from 6am on Thursday until the end of Easter Monday.
However, for safety reasons lane restrictions or temporary speed limits will need to remain at 69 locations.
Ferry companies have warned of long delays once the checking of passports for those leaving the country is introduced on April 8.
The companies have spoken of hold-ups on roads to Dover with "coach-loads of grannies" having to have their passports checked.
Immigration Minister James Brokenshire has advised travellers to set off in good time.
But he said he did not recognise the "extreme" stories about how the changes could impact travellers and insisted there were contingency plans ready.
The AA said Thursday is likely to be the busiest day on the roads.
An AA/Populus survey of more than 16,000 AA members showed that 47% plan a drive of some kind on Thursday, with 44% likely to take to the roads on Good Friday.
Those planning a leisure trip by car will cover an average of around 40 miles on Thursday, with Londoners clocking up the biggest distance (45 miles), followed by those in Yorkshire and Humberside (43 miles) and East Midlands (42 miles).
Those in south east England will have the shortest journeys (38 miles).
According to Trafficmaster, the top five busiest stretches of road are likely to be:
A303 westbound through Hampshire, Wiltshire and Somerset
M1 from junction 6A (M25 interchange) to junction 13 east of Milton Keynes in Buckinghamshire and from junction 23A in Leicestershire to junction 32 south of Rotherham on Yorkshire
M5 from junction 15 north of Bristol towards junction 31 (Exeter for the West Country)
M6 through West Midlands (from junction 4A) and northwards towards Lancashire (junction 21A)
M25 all sections, especially both ways around junctions 14-17 around Heathrow airport.
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