Meet the site
Hole in the Wall is a large sea cave in the limestone reef close to The Gap in Dhilba Guuranda-Innes National Park. The Marine Life Society describes a cave about 40 m wide extending roughly 70 m under the reef, with a sandy bottom, and calls it a 'big cave' with some tight squeezes. It is typically dived on the same tank as The Gap, about 100 m away. The cave interior is lined with sponges, gorgonians and soft corals that thrive in the shaded, surge-fed environment, and it shelters western blue groper, southern blue devils, wobbegong sharks and other reef fish. Light filtering through the entrance creates dramatic silhouettes, and the sandy floor makes navigation relatively straightforward in the main chamber. A torch is required, and the Marine Life Society warns that the tight squeezes are not for newer divers. The main chamber is wide enough to feel open, but it is still an overhead environment, and the surge that feeds its invertebrate growth can make it dangerous in any swell. Hole in the Wall suits advanced divers with good buoyancy and some experience of caverns or swim-throughs, visiting by boat on calm days. Combined with The Gap, it offers one of the most distinctive dives on the Yorke Peninsula coast. Plan the pair as a single, well-briefed dive: agree on turn pressures before entering the cave, keep buddy contact inside where silt can lift from the sand floor, and leave enough gas for the swim along the reef to The Gap. Photographers should bring wide-angle lenses – the contrast between the blue entrance and the sponge-covered interior walls is the shot most divers come home with. Because both sites face south into the swell, check conditions from the Gap lookout by car the day before if you are staying in the park.
What you might see
Western blue groper, southern blue devils, wobbegong sharks, sweep, bullseyes, sponges, gorgonians, soft corals
Location
Large sea cave set into limestone reef about 100 m from The Gap in Innes National Park – roughly 40 m wide and extending about 70 m under the reef, with a sand floor, in 10-15 m.
Facilities nearby
Marion Bay and Pondalowie Bay ramps.
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.