A landslide on the Kings Highway on Friday has led to a flood of Canberrans cancelling their holiday plans.
Work has begun on Clyde Mountain to examine the extent of the damage after several hundred tonnes of rock and debris crashed to the ground just near Pooh Corner.
The highway will remain closed until at least tomorrow while investigations are carried out to determine the stability of the area and degree of repairs.
A NSW Roads and Maritime Services spokeswoman said clearing the site would begin once the area was stabilised.
There were still rocks and debris falling on Friday night, she said.
Motorists are being diverted to Nerriga Road, via Bungendore and Braidwood, to Nowra.
Araluen Road is also closed in both directions due to road damage.
Batemans Bay businesses are reporting cancellations from Canberrans not willing to double their driving time to reach the coast.
ACT school students remain on holidays for another week and the south coast is a popular destination.
Batemans Bay Beach Resort's Kerry Flower said the resort had been fully booked for the annual Anzac regatta this weekend.
''Basically we've had numerous cancellations because people aren't prepared to drive the distance,'' she said. ''It's taking 4½ hours instead of two.''
Bayside Motel owner Guy Smith said he had only had a few cancellations but usually picked up business during the weekend.
''Saturday nights we normally get quite a few bookings from Canberra … they just haven't been able to turn up,'' he said.
Heavy vehicles are being advised to use the Hume Highway or the Snowy Mountains Highway.