Meet the site
Skull Rock, officially Cleft Island, is the great granite dome that stands alone in Bass Strait west of the Anser Group, hollowed on its northern face by a sea cave large enough, as the Prom cruise operators like to say, to hold the Melbourne Cricket Ground. Seen from the sea the eroded hollow and the two dark overhangs give it the look of a skull, and it has become the symbol of the Prom's wild south. Underwater it is, in Scuba Doctor's words, awesome diving: the rock rises 113 m above the water and the granite continues 65 plus metres below it as near-vertical walls, with underwater caves, and it is rated Deep/Technical for that reason. The dive is a wall dive in the purest sense. Below a fringe of bull kelp in the surge zone the granite drops sheer or in giant steps, and because there is no shelter from swell or current every surface below 15 m is covered in filter feeders – sponges in every colour, yellow zoanthids, gorgonian fans, sea whips, jewel anemones and bryozoans – in a density that only the most exposed sites in Victoria achieve. Fish hang off the wall in clouds: butterfly perch, barber perch, sweep and bullseyes close in, with kingfish, salmon and the occasional sunfish in the blue. Australian fur seals from Kanowna and the Anser Islands haul out on the lower ledges and, the listing notes, frequently interact with divers. Visibility is often 20–30 m, the clearest water on the Victorian coast. The caves at depth are large granite overhangs and clefts rather than true cave systems, but they and the seals give the shallower part of the dive its character. Everything about Skull Rock is demanding except the diving itself: the site is remote, the walls invite depth, the current runs, the seas are often wild, and it is reached only by a well-found private or club boat on a rare calm day. Parks Victoria's Wilsons Promontory Cruises run sightseeing boats to the cave from Port Welshpool, which is how most people see it. For divers with the boat, the weather and the experience, it is the finest wall dive in Victoria.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Skull Rock is recorded as Wall in Wilsons Promontory. The listed access is boat. Confirm the actual meeting point, route and permission to visit; a map pin does not establish any of these.
Topics flagged by the stored research
These are questions prompted by the existing notes, not a verified or complete hazard assessment.
- Current and timing
- Ask how the operator assesses the current window for the actual route. Historical tide notes are not a departure instruction.
- Other water users
- Ask about vessel activity, exclusion areas and the agreed surface arrangements.
- Lines and obstructions
- Discuss any known entanglement concerns and the suitability of the planned area.
- Planned depth
- Confirm the intended route and training requirements; the recorded maximum is not a target.
- Water movement
- Ask how swell and local exposure affect the proposed entry, exit and route.
Historical access notes exist for this record, but have not been independently verified for current use. Request current directions from the operator or site manager rather than following an old entry description.
Questions, answered
Is Skull Rock suitable for my certification?
The record lists Technical (decompression). That does not establish suitability for every route or day. Share your training, recent experience and equipment needs with the operator and ask about the specific proposed dive.
Can I book Skull Rock through YouDive?
YouDive is an independent research directory. Contact an operator directly to confirm whether it currently runs the trip, the inclusions and the booking terms.
What you might see
Australian fur seals, sponge gardens, zoanthids, gorgonians and sea whips, jewel anemones, bull kelp, butterfly and barber perch, sweep, bullseyes, kingfish, sunfish occasionally, great white sharks recorded
Location
Isolated 113 m granite island with a vast sea cave, about 5 km west of the Anser Group and 10 km south-west of the Prom's South Point, in the Wilsons Promontory Marine National Park.
Facilities nearby
Departure from Tidal River beach ramp, Port Welshpool or Sandy Point; No air fills at Tidal River or Port Welshpool; the nearest compressor is roughly 100 km away (Melbourne's south-east or Inverloch/Leongatha area by arrangement) – bring all cylinders or a portable compressor
Before you make plans
Conditions, access and operator schedules can change. This is a location guide, not a dive plan. Ask a local operator about current conditions and suitability for your training and experience.
Sources & further reading
scubadoctor.com.auscubadoctor.com.auweareexplorers.coen.wikipedia.orgRecord updated 27 Sept 2026. Source claims are being reviewed.