We drove the Great Ocean Road this past June with the family. Give yourself 2 days and you will have plenty of time to see the highights at least through Port Campbell and not feel rushed. Just a few miles past Port Campbell is what remains of the collapsed stone bridge. If you try to squeeze the drive into 1 day, you will definitely feel rushed.

Walk the entire boardwalk at the 12 Apostles as the views of the Apostles change dramatically from one end of the boardwalk to the other.

The boardwalk and (make sure to walk down to the beach cove as most people miss this) at Loch Aird is actually quite nice. We stopped here with the kids and walked around and the kids played on the beach for a while. Great place for a beach picnic.

Onedog