The A83 at the Rest and be Thankful in Argyll has reopened after being closed by a landslip for the seventh time in five years.
Heavy overnight rain across the west of Scotland washed about 100 tonnes of rubble on to the carriageway.
Engineers have been working throughout the day to make the road safe.
The landslip occurred too far west for motorists to use an emergency diversion route which was opened in February along an old military road.
The road, which reopened at 17:30, had been closed between the A815 and the B828.
Contractor Bear Scotland said a further section of the road, at the top of Glen Croe, south of the Rest and Be Thankful car park, had also been affected by a "debris slide".
The company said it would continue to work on some sections of the A83 overnight, so drivers may experience slight delays.
The situation was to be monitored overnight and on Friday morning.
Brian Gordon, Bear Scotland's managing director, said: "Our team has worked flat out in difficult conditions to re-open the road. We are doing so with traffic controls and a number of other safety measures in place given the on-going poor weather forecast.
"As always the safety of motorists is our utmost priority and we will ask anyone experiencing delays to be patient while we continue to monitor the situation throughout the night."
The Met Office has warned that heavy rain will continue throughout the night, with 28-30mm of rainfall expected.
Earlier, the company said geotechnical experts had to confirm the stability of the slope to ensure the safety of the workers carrying out the clear up operation.
The firm said "a number of excavators, clear-up vehicles and around 25 Bear engineers and operatives" were on site.
During previous landslips, motorists have been forced to undertake diversions of up to 50 miles.
Transport Minister Keith Brown said: "We know that the A83 is a vital route for people living and working in Argyll and Bute and our operating company, Bear Scotland, has deployed all of its resources to clear the hundred tonnes of rock and mud from the road at Glen Kinglas as quickly as possible.
"The slip at the Rest and Be Thankful was much smaller and unfortunately another slip caused some debris to fall on the Old Military Road which is used as a diversion route for the A83. This wasn't brought into play today as the main landslide was too far west for it to be used.
"Landslides are naturally occurring events, we can't stop them happening but we can lessen the impact and we have been making improvements, not only to our processes but also through engineering. There are no overnight solutions to the issue but we are committed to a programme of on-going works to remedy the situation.
"We have invested £3.7m in mitigation measures on the A83 including protective netting, a new culvert and drainage system at the site of a previous landslide and geotechnical monitoring equipment.
"This area at Glen Kinglas is part of the further studies we are undertaking on the A83 to find solutions to the unique challenges that the route poses."