Rail services are going to be affected this weekend due to the Midland Main Line upgrade.
On Saturday and Sunday (March 19 and 20), engineers will be upgrading the overhead line equipment - which is used to power some trains - south of Bedford.
This is the first of several weekends where the railway will be closed so that Network Rail teams can boost the power supply safely.
Limited services will run between Luton and Bedford on Saturday, with buses replacing all trains between the two towns on Sunday.
Gary Walsh, East Midlands route director for Network Rail, said: “We’re at a really exciting stage of the Midland Main Line upgrade, which will see us boost the power supply south of Bedford and take us one step closer to delivering better, more reliable journeys for passengers.
“Although we've packaged multiple projects together to keep disruption to a minimum, I’d advise anybody who needs to travel to check their journey in advance as there will be some changes to train services.”
Jenny Saunders, customer services director for Thameslink and Great Northern, said: “All day on Saturday and Sunday this coming weekend, buses will replace our Thameslink trains between Bedford and Luton, with journeys taking up to 30 minutes longer.
"If you’re one of those affected, then please allow yourself extra time to travel.”