Vivonne Bay has been voted one of Australia's best beaches, a 5 km curve of white sand on Kangaroo Island's south coast. At its western end a 79 m jetty runs out beside Point Ellen, an 8.5 m mound of Pleistocene dune limestone ringed by rocks that shelters the western corner of the bay from swell. Tourism Kangaroo Island calls it the safest of the south-coast spots, best around the jetty and towards Point Ellen, with southern goatfish, smooth stingrays and dusky morwong; Wander adds brilliant azure rock pools.

The jetty is small, but its pylons and the adjoining reef support a mix of jetty and reef life: sponges and algae on the piles, kelp-covered limestone towards the point, rays on the sand, goatfish rooting in the sediment and schools of sweep and leatherjackets. Rock lobster shelter under ledges, and sea lions occasionally visit from colonies along the south coast. Visibility is often excellent in calm conditions, thanks to the clean Southern Ocean water. Bay depths are generally 9-11 m offshore.

The caveat is the south coast itself. The bay has a significant undertow and sizeable swell at times, and in 2011 two tourists drowned when a wave swept them from Point Ellen. Tourism Kangaroo Island stresses checking conditions on arrival and throughout. The jetty corner gives a real chance of a dive on the south coast, but only on calm days. It suits snorkellers and Open Water divers who respect the sea, and it is a pleasant stop with the Vivonne Bay general store nearby.

Take the SeaLink ferry from Cape Jervis to Penneshaw (45 min). From Kingscote drive about 1 hour south-west via the Birchmore/South Coast Road to Vivonne Bay (sealed), then follow signs to the jetty and boat ramp at the western end of the beach near Point Ellen. Park at the jetty car park, gear up and enter from the beach beside the jetty or from the jetty steps.

Tourism Kangaroo Island recommends snorkelling around the jetty towards Point Ellen.

Kangaroo Island's south and west coasts face the open Southern Ocean and take the full force of prevailing south-westerly swells, commonly 2-5 m and bigger in winter. Diving is only possible in rare windows: swell under about 1-1.5 m, light northerly or north-easterly (offshore) winds and several settled days, most often in late summer and autumn (February-May). Rips and undertow are strong on the beaches, and wave surge reaches the bottom at recreational depths.

Conditions can change within hours as fronts arrive – check the Bureau of Meteorology coastal forecast and swell models, and have a sheltered north-coast alternative. The jetty corner is the most sheltered part of the bay thanks to Point Ellen, but significant undertow and swell occur at times; two tourists drowned in 2011 when a wave swept them from Point Ellen.

Enter beside the jetty, snorkel or dive along the pylons and then the reef edge towards Point Ellen in 3-8 m, staying inside the shelter of the point, and return to the jetty.

No regular operator – independent.