Network Rail has released timelapse footage showing the 24-hour-a-day operation to clear the massive landslip that closed a section of the railway for almost six weeks.
Some 350,000 tonnes of cutting collapsed near Harbury Tunnel in Warwickshire on Saturday 31 January this year.
This meant the railway had to be shut between Banbury and Leamington Spa, affecting a number of long-distance services.
Network Rail has now reopened the railway with reinstatement of services between Birmingham and London; and between the South Coast and the North of England.
Network Rail chief executive Mark Carne said: “The reopening of the railway, three weeks ahead of schedule, is welcome news for passengers and freight operators. It is also a testament to the hard work of hundreds of people who have worked 24 hours a day to make it possible.
“Everything was done to reopen this essential line – which is relied upon by thousands of passengers every day and used to transport thousands of tonnes of freight – as safely and quickly as possible.
“I thank passengers and the residents of Harbury for their patience while we carried out this vital work. I can assure them that the ongoing repairs being made are long-term solutions which will significantly reduce the chances of similar incidents in the future.”
Harbury cutting has suffered from landslips since it was built more than 150 years ago.
Network Rail will now remove more than 300,000 tonnes of material to regrade the slope of the cutting, making it more stable.