A derailed train which is resting over a 15-metre embankment in Argyll could be removed by the end of the week, Network Rail has said.
The firm hopes to have a crane in place by Thursday or Friday to remove two carriages from the line near the Falls of Cruachan power station by Loch Awe.
The route may not open until next week, however, to allow for track repairs.
Fallen rock is thought to have forced the Glasgow to Oban service off the line shortly before 2100 BST on Sunday.
All 60 passengers on board were safely rescued with eight taken to hospital with minor injuries.
A spokesman for Network Rail said the firms engineers had been inspecting the scene with officers from the Rail Accident Investigation Branch.
The firm, which operates the UK's tracks and signalling system, hopes to have a crane at the site in the next 48 hours.
An operation would then commence to clear the two carriages from the embankment overlooking the A85, which is also closed.
Damage caused to the track from fallen rocks, however, means that line repairs could prevent trains running on the route until next week.
BBC Scotland understands that "big boulders" found on the railway line may have come from just several feet above the track and not have fallen from a great height.
A trip wire system, in place to detect landslides further up the embankment, was not triggered.
The warning screen, which runs for four miles over the affected stretch of track, is designed to alert train drivers to obstructions on the track.
It was last inspected on 4 April and is checked at regular 90 day intervals.
The track was inspected on 26 May and is checked every two weeks.