The Great Ocean Walk is the backbone here, a point-to-point oceanside ultra that grew out of the old GOW100 and still sounds like it has kept its grassroots bite. The route heads for the Twelve Apostles country, with the 12 Apostles Visitor Information Centre the intended finish area and Princetown Recreation Reserve used when finish logistics shift. It earns the line "Australia’s most iconic oceanside ultra" because a lot of this is wilderness you just can't see from the Great Ocean Road.
Underfoot it is mostly real trail: about 73% singletrack, 20% fire trail and gravel, with short beach and pavement sections breaking it up. That mix matters late, because the "sweetest singletrack anywhere" still has to be run when your legs are already busy negotiating coastline, forest, sand, and cutoffs. Trail runners come to race it, bushwalkers normally take days over the same ground, and the finish has its own plain-spoken tradition: they are famous for finish line hugs.