The way I would go is this route. It's at least 45 minutes and 40 km shorter than the Nerriga route. It's great route for those with a well balanced rig. It's great country through Kangaroo Valley. I used it frequently rather than the Clyde when I dived in the ACT (that was the days before the Nerriga road was sealed, these days I would still use it for Kiama to Goulburn.)
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.