Rail passengers face disruption this weekend if they are travelling to London on Midland Mainline services.
Work on the Channel Tunnel rail link means services from Nottingham will terminate at Luton on both Saturday and Sunday, a spokesman said.
Passengers will be able to travel between Luton and London's King's Cross station by changing onto First Capital connect services at Luton.
There are also changes to the timetable affecting these services.
Passengers are being advised to check train times before travelling.
And the RMT trade union has announced a 24-hour national rail strike from noon starting on 21 July.
A second 48-hour strike is planned for 27 and 28 July.
Midland Mainline said it will run as many services as possible on those days.