Southwest Australia has an incredible shoreline exposed to the Indian Ocean on both the west and the south. Leeuwin National Park sprawls up and down the coast on the western edge of the westernmost (I think) bulge of southwest Australia, north of Flinders Bay and south of Geographe Bay. With literally thousands of kilometers of open ocean to the west in which waves can build, it's no wonder it's popular with surfers. It's apparently popular with dolphins also, as we saw some of them enjoying the surfing as well.
This region is underlain by a lot of limestone, and when water trickles down through limestone, you get caves. We spent a few hours in the afternoon at one of them, Ngilgi Cave.