By james art Network Rail said it expected the Cambrian line to be open for normal services from Monday.
It comes after one person died and 15 others were injured when two trains crashed near Llanbrynmire in Mid Wales on Monday night. The deceased is Tudor Evans, aged 66, from Aberystwyth.
Network Rail said investigation teams have now completed their on-site investigation.
This allowed Transport for Wales (TfW) engineers to reach the crash site and separate the two damaged trains, which are in the process of being removed from the site.
At the same time, Network Rail engineers carry out repairs, maintenance and a series of safety checks and inspections.
A statement from Network Rail sought to reassure the public on the line, saying: “The safety systems of trains using the line continue to be regularly checked and inspected.
“Test trains will run through the area to make sure everything is working properly before passenger operations start on Monday.”
But, he said, the incident could still affect train services in the short term and passengers should continue to check before travelling.
Nick Millington, Network Rail’s Wales & Borders route director said: “The tragic events of Monday night will live forever in my memory and my thoughts are with all those affected.
“Fortunately, incidents like this are extremely rare on the rail network. We continue to operate one of the safest rail networks in Europe.
“Our engineers have been on site throughout and have carried out very thorough safety checks and we will be running test trains in the area.
“I am grateful to the local community who have been very responsive over the past week as we have dealt with this incident.
“I would also like to thank passengers for their patience, understanding and support over the past few days as our teams worked tirelessly to restore the railway as quickly as possible.”
Jan Chaudhry van der Velde, TfW’s chief operating officer, said: “Railways in Wales have a very good safety record, so when serious incidents like this happen, we at TfW, together with our partners at Network Rail, are determined to get to the bottom of what caused it.
“We are therefore co-operating fully with the authorities investigating the collision, and in particular with the Rail Accident Investigation Branch.”
“We have been working hard to clear the trains safely from the scene and carry out full inspections and safety tests before reopening the line to passenger trains.
“Our condolences go out to the family of the deceased passenger and we hope those passengers and crew members injured in the collision make a speedy recovery.”
Network Rail said that due to “operational challenges” following the incident, there will be no TfW services between Shrewsbury and Birmingham International this Saturday or Sunday.
He confirmed that ticketing had been arranged with West Midlands Rail along the route, but added that people were being advised to use alternative routes where possible.