Cape Torrens marks the highest coastal cliffs in South Australia – 263 m of sheer rock on Kangaroo Island's north-west coast, protected in a wilderness area. The Marine Life Network describes spectacular drop-offs underwater, to 40 m, with abundant life.

The walls carry zoanthids, gorgonians and sponges in vivid colours, with the diversity typical of the island's clean, cold water. Blue groper, kingfish and sea dragons are listed among the fish, and seals and dolphins frequently join divers – the north coast operator Kangaroo Island Dive & Adventures reports seals on about 90% of its dives and dolphins on about 60%. Because the site is so remote and rarely visited, fish are large and approachable, and the scale of the cliffs above is matched by the depth below.

The Portland Maru wreck lies just to the west, making it possible to combine a deep wall dive with a shallower wreck dive. The remoteness is also the main caution: the nearest launching point is Stokes Bay, the nearest town Kingscote, and the nearest chamber is Adelaide by aeromedical retrieval. With depths to 40 m, conservative planning and nitrox are sensible. It suits experienced, well-equipped boat divers wanting one of South Australia's most spectacular and least visited wall dives. Anyone planning a trip should organise it as an expedition: two boats if possible, a detailed float plan lodged with someone ashore, and a fallback site such as Western River Cove or Stokes Bay if the swell or wind turns. Surface intervals under the cliffs, with seals and dolphins around the boat, are part of the experience.

Take the SeaLink ferry from Cape Jervis to Penneshaw (45 min), then drive west via Kingscote and the North Coast Road; the western north-coast sites are 1-1.5 hours from Kingscote on partly unsealed roads (red dirt, corrugations). Cape Torrens is part of a wilderness protection area with no road access to the water, so diving is by boat only – from Stokes Bay (the nearest launching point) or with a Kingscote operator on an extended north-coast trip. It is a long run along an exposed coast with no shelter; carry marine radio and ample fuel.

Kangaroo Island's north coast faces Investigator Strait and is sheltered from the prevailing south-westerly Southern Ocean swell, so it is the island's most reliable diving coast. It is exposed to northerly and north-westerly winds and swell, which bring surge, poor visibility and dangerous entries – dive on southerly to south-easterly winds or after a few days of southerlies. Summer and autumn have the most settled weather; winter fronts bring north-westerlies before they pass.

Visibility is often 10-20 m in good conditions. Mornings are calmer before sea breezes.

Drop onto the top of the drop-off, descend the wall to your planned depth (25-30 m on air), work along it and ascend slowly up the face to a safety stop in the shallows; watch for seals and dolphins on the ascent.

Nitrox recommended; plan for no nearby assistance – carry oxygen and a DAN kit on the boat.

No regular operator – occasional private and club expeditions; ask Kangaroo Island Dive & Adventures.