A landslip is blocking a railway line between the East Sussex coast, Kent and London.
Trains will not run between Robertsbridge and Tunbridge Wells until Monday "at the earliest" due to the slip at Wadhurst, Network Rail said.
There are 60 tonnes of mud and trees to remove before the cutting can be inspected for damage.
Work was delayed for safety reasons while engineers waited for "the earth to stop moving," the company said.
Here's what we're dealing with at Wadhurst, a huge landslip which continued moving overnight. Geotechnical engineers are inspecting the site now before coming up with an action plan to repair the cutting and restore services. pic.twitter.com/QBjFwzScQ5— NR South East (@NetworkRailSE) March 14, 2019
Heavy machinery is to be delivered to the site by road and clearance work will begin on Friday.
The line, which runs between Hastings and London, via Tunbridge Wells, was blocked in both directions after the landslip on Wednesday afternoon.
Southeastern and Network Rail have apologised to customers and said the safety of those on the railway is their priority.
A spokesman for Southeastern said: "We strongly advise passengers to find alternative routes and postpone journeys where possible.
"We will be operating a replacement bus service between Robertsbridge and Tunbridge Wells and a shuttle train service between Hastings and Robertsbridge."
Passengers travelling from stations south of Tunbridge Wells can use their tickets on high speed services from Ashford International, the Southeastern spokesman said.
"We will provide further updates as soon as we can, but in the meantime please check for the latest information before you travel."
A Network Rail spokesman said: "We cannot give a definitive timescale, but expect the route between Robertsbridge and Tunbridge Wells to remain closed for several days."