With Easter looming, the NSW Government has produced a "Holiday pinch points in focus" guide for those preparing to brave the highway over the long weekend.

It says delays of 30 minutes and over are possible for two days for those travelling westbound, while the highway is likely to be busy all day Monday, April 1 for those travelling eastbound.

The warning comes after there were two crashes on the highway, at Blackheath and then at Hartley, in just 90 minutes recently.

It also comes as work continues on duplications of small sections of the highway at Little Hartley (worth $232 million) and Medlow Bath (worth $174 million).

At the latter, the construction site itself is also affecting traffic.

Westbound

Eastbound

The Easter weekend traffic guide says the Great Western Highway and Govetts Leap Road intersection in central Blackheath is a key pinch point location for those returning to the Sydney area at the end of holiday periods and ordinary weekends.

"During the Easter break, a significant amount of traffic travels out of Sydney and west on the Great Western Highway and returns at the end of the long weekend," the guide says.

"When vehicles begin to queue eastbound at Mount Victoria, a traffic management plan is put in place to prevent breakdowns on Victoria Pass.

"Motorists are held at Hartley, the base of Victoria Pass, to prevent traffic congestion, breakdowns, and start/stop movement up the Pass.

"Vehicles are then released in small groups, allowing them to travel up the Pass in one smooth movement, and preventing delays due to breakdown."

IN an update on work on the Great Western Highway duplication at Medlow Bath, Transport for NSW says the project remains on track to be completed in early 2025.

The update says pavement work has started on the eastbound side of the highway adjacent to the rail line and once this is complete, towards the middle of the year, traffic will switch over to that side of the highway so the construction crew can work on the westbound side of the road.