Football fans are being warned of long wait times if they are travelling by train to Wembley this weekend.
The quickest rail route between Birmingham and London for the 38,000 Aston Villa supporters travelling to Saturday's Championship play-off final against Fulham, will be blocked.
Network Rail is carrying out a major signalling project between Birmingham New Street and Coventry.
Chiltern Railways has added extra capacity to its London-bound route.
Rail bosses said wait times may be longer than the match itself, with delays expecting to last 90 minutes or longer.
'Never a good time'
Extra staff will be deployed to deal with the crowds.
Shrewsbury Town and Coventry City are also playing at Wembley over the bank holiday weekend, in the League One and League Two play-off finals respectively, and their fans are also being urged to plan ahead.
Eleni Jordan, Chiltern Railways commercial director said: "Customers travelling to Wembley over the weekend should be aware that queuing systems will be in place at Birmingham Moor Street, London Marylebone and Wembley Stadium stations, and there may be queues of 90 minutes or longer in both directions."
Martin Frobisher, a route managing director for Network Rail, said: "Improvement work on the railway is planned years in advance, ahead of any short-term scheduling of sporting events and knowing which teams will compete in finals.
"There is never a good time to carry out big pieces of work but we plan it over bank holidays - which are traditionally quieter times - to affect the fewest number of people."