Meet the site
Three Hummock Island, in the Hunter Group off Tasmania's north-west tip, is rated 7 out of 10 by the Marine Life Network guide as a remote adventure with rugged coastal scenery. The island is granite - rare on the north-west coast - and at Chimney Corner large cubed boulders form swim-throughs in 10-15 m. Old wives and small crayfish are recorded, with a variety of fish and invertebrates in the crevices and deep drop-offs along parts of the shoreline. The guide describes it as extremely remote and still being explored, and it also mentions nearby Trefoil Island, dived only on its eastern side in easterly weather, as another Hunter Group prospect. Above water the island is a place of rugged granite headlands, and landing requires the leaseholder's permission. Expect to be entirely self-sufficient for a trip here, with a sounder, radio, EPIRB and spare fuel, and a plan for sheltering if the weather turns.
Circular Head, the far north-west corner of Tasmania around Stanley and Smithton, faces the full sweep of Bass Strait and the tidal flows that pour between the mainland and the Hunter Group islands. Few divers visit: there is no dive shop or air station west of Burnie that can be confirmed, so divers bring everything with them, and the Royal Hobart Hospital chamber is around five hours away by road. The reward is clean, rarely dived water and marine life that includes species more typical of Victoria and South Australia, such as warty prowfish and weedy seadragons in the sheltered bays.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Chimney Corner (Three Hummock Island) is recorded as Island in Tasmania North & North-West. The listed access is boat. Confirm the actual meeting point, route and permission to visit; a map pin does not establish any of these.
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 Chimney Corner (Three Hummock Island) suitable for my certification?
The record lists Advanced Open Water. 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 Chimney Corner (Three Hummock Island) 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
Old wife, small crayfish, reef fish, crevice invertebrates
Location
Granite boulders forming swim-throughs at Chimney Corner on remote Three Hummock Island, in the Hunter Group off north-west Tasmania.
Facilities nearby
None on the island (private lease/reserve). Smithton: shops, fuel, ramp.
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
marinelife.org.auRecord updated 26 Sept 2026. Source claims are being reviewed.