Buses will replace trains from Corby, Kettering and Wellingborough this weekend as part of a major railway upgrade.
On April 28 and 29 Network Rail engineers will carry out work at various locations along the Midland Main Line, causing significant changes to train services.
Preparation work for the installation of a fourth track between Bedford and Kettering will take place to increase capacity, including the strengthening of several key structures between the two towns.
Work will take place on bridges in Corby, Wellingborough and Bedford meaning East Midlands Trains services will be replaced by buses between Luton and Leicester and Thameslink services will be replaced by buses between Luton and Bedford.
Rob McIntosh, route managing director at Network Rail, said: “Over the weekend of April 28/29, Network Rail engineers will be doing a huge amount of work to the railway in the East Midlands.
“The work will see track improvements and three bridge demolitions as part of the Midland Main Line upgrade, which will ensure we can continue to meet the needs of the communities and economies that our railway serves.
“Due to the nature of the work, there are significant changes to train services and passengers are advised to check before they travel via National Rail Enquiries and allow additional time for their journeys.
“We’d like to apologise for any inconvenience this causes and thank rail travellers for their patience.”
Passengers travelling from Kettering and Wellingborough will have to get a bus to Luton or Leicester before continuing their journey by train.
Passengers travelling from Corby will get a bus to Kettering before then taking the northbound or southbound bus.
Adam Piddington, customer experience director for East Midlands Trains, added: “This investment will provide better journeys in the near future but there is some short term disruption while the work is carried out.
“We will have staff on hand to help customers but I would also ask everyone to check the temporary timetable before they travel and, if possible, leave a little extra time for their journey.”