Milton Keynes passengers are being warned to travel either side of the bank holiday weekend as major works take place at Euston.
Between Good Friday (7 April) and Easter Monday (10 April), Euston station will be shut to main line train services for the final phase of upgrades to track and signalling at Watford junction.
As this work needs the entire railway to be closed over the four-day long weekend, trains will start and finish at Milton Keynes instead.
Rail replacement bus services will be in place to connect passengers with other main lines into London.
Dave Penney, Network Rail passenger director for the North West and Central region, said: “We're reminding people that the best time to travel on the West Coast main line and Chiltern main line this Easter is on Thursday 6 and Tuesday 11 April - before and after we must close parts of the railway to carry out multi-million pound improvement work.
“This advice becomes even more pertinent with the urgent closure of a railway viaduct south of Oxford used by CrossCountry services, as the knock-on impact over the Easter weekend will make alternative routes very busy. Please check with your train operator directly if you think you could be impacted by that - especially if you have booked assisted travel.”
Passengers should plan ahead at www.nationalrail.co.uk or check with their train operator for the latest journey information.