Rail services have ground to a halt in parts of the country today (Wednesday) as a fresh wave of strikes begin, the BBC said on Wednesday.
The government said the strikes were co-ordinated to disrupt major events.
Wednesday's strikes will affect 15 train companies, with services due to start later and finish much earlier than usual - typically between 07:30am and 06:30.
Around 40% of trains will run but there will be wide regional variations, with some operators running no services at all. During the RMT's action on Friday around half of the network is set to shut down.
Thousands of passengers will face disruption including those planning to go to the FA Cup final between Manchester City and Manchester United at Wembley and the Epsom Derby on 3 June, other local media reported.
Aslef drivers will walk out again on Saturday, affecting the first ever all-Manchester FA Cup final at Wembley and the Scottish cup final at Hampden Park.
That strike will also impact Beyoncé's Renaissance world tour concert in London; the England v Ireland cricket test match at Lord's; and some 100,000 horse racing fans travelling to Epsom for the Derby.
Business is also counting the cost of the long-running industrial action.
Tristan Moffat, owner of the Piano Works bar in London, told the BBC "nothing has hit us harder".
"The train strikes really are crippling to the business, and in a time when we're already seeing so many businesses on the knife edge and up against the wall we need a period of stability."
KI/PR