Revellers attending Reading Festival are set to be hit by rail strike action from Saturday to Monday by members of the Rail, Maritime and Transport union as First Great Western passengers travelling towards the South West will face reduced services.
Planned works by Southern mean trains will be disrupted from the south coast and Surrey into London from Saturday to Monday.
On Sunday buses will replace trains between Bicester North and Banbury, significantly increasing journey times from the Midlands and Oxfordshire to London.
National Express is adding 67,000 extra seats to its coach network for travellers looking for an alternative method of transport in the face of rail disruption.
A spokesman for the operator said: “Demand for coach services has significantly increased on affected routes and bookings have increased by nearly 30% year-on-year in affected areas.”
He added that some journeys, such as from Bournemouth or Poole to Heathrow Airport, would be quicker by coach than train as a result of the rail disruption.
Some 148,000 passengers are set to travel on the Eurostar over the bank holiday weekend, with 38,000 travelling on Friday alone.
Highways England said it was removing more than 400 miles of roadworks from motorways and major roads in a bid to reduce hold-ups.
Some 177 sets of roadworks will be completed or lifted in time for the late August getaway.
The section of the A27 hit by a plane in the Shoreham air disaster is currently closed and diversions could remain in place on the popular coastal road into the weekend.
A spokesman for the Rail Delivery Group, which represents operators and Network Rail, said: “Rail staff work all day, every day to maintain and improve the network, but times when fewer people are travelling - such as the August Bank Holiday weekend – are a chance to carry out big pieces of work that can’t be squeezed into usual night times when trains aren’t running.
“Train operators and Network Rail have been working together closely to minimise disruption to passengers, to let people know if their journey will take longer than normal and to keep people on trains not replacement buses wherever possible.”
He advised passengers to check nationalrail.co.uk before they travel, but added that the majority of people’s journeys are expected to be unaffected by improvement works.