5.40PM UPDATE: Heavy traffic on the Princes Highway at Berry, Milton and the Kiama Bends has now eased and there are no longer significant delays for motorists travelling in these areas.
3.50PM: Holiday traffic is causing delays at Kiama, Berry, and Milton.
In Kiama, southbound traffic on the Princes Highway is queued seven kilometres adding 40 minutes to drivers' trips at the Kiama Bends.
In Berry, southbound traffic on the Princes Highway is queued one kilometre but northbound traffic has now eased.
In Milton, southbound traffic on the Princes Highway is queued back two kilometres adding about 15 minutes to travel times.
In the Royal National Park, Garie carpark is full and drivers are being asked to avoid the area.
The Transport Management Centre advised drivers to plan ahead and allow additional travel time.