Meet the site
Tommy Grahams is the Nullarbor cave rated 'Cave' (rather than Advanced Cave) by the CDAA, but it is no easy dive. The CDAA site description traces a steep entrance slope down a nearly choked rockpile into the main chamber and a small lake, then a 190 m sump through a phreatic maze to an 80 m dry chamber with another lake. Beyond, Glacier Lake leads 130 m to a 30 m-diameter rockpile chamber blocked 35 m above the water.
A TDI trip report adds detail: the first sump reaches an official 30 m depth (the team recorded 36.4 m), with named passages including The Keyhole, The Five Ways, The Blue Room – which has an amazing halocline – and The Slot. The dry 'Inner Sanctum' has high CO2, so divers breathe from their cylinders or rebreathers while crossing. Water and air in the cave are a relatively warm 24°C.
The cave was explored from Christmas 1973/74, with about 1,300 m added in the early expeditions; the final rock pile could not be passed in 1975. Divernet notes that only 50-60 people have reached the furthest point, and that the system may extend for many kilometres.
The entry is brutal – a restriction called The Birth Canal and a 55-degree slope – and the site is remote. Divers must apply to DBCA Esperance four weeks ahead. Teams typically base themselves at Cocklebiddy and allow several days for the hauls, dives and recovery. Rebreathers make the Inner Sanctum crossing and long dives more manageable.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Tommy Grahams Cave is recorded as Cave/Cavern in Nullarbor Caves. The listed access is shore. 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.
- 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.
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 Tommy Grahams Cave suitable for my certification?
The record lists Cave/Cavern certification. 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 Tommy Grahams Cave 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
Stygofauna; no fish
Location
Nullarbor cave about 30 minutes off-track from Cocklebiddy, with a steep entrance rockpile, a 190 m first sump to 30-36 m through a phreatic maze, the CO2-rich 'Inner Sanctum' and a 130 m second sump from Glacier Lake; warm 24°C water.
Facilities nearby
None at the cave; Cocklebiddy Roadhouse 30 minutes.
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
tdisdi.comcavedivers.com.audivernet.comcavediving.net.auen.wikipedia.orgRecord updated 26 Sept 2026. Source claims are being reviewed.