Helga's Tunnels

Meet the site

Helga's Tunnels is one of the named Lighthouse Bay sites alongside Blizzard Ridge, The Labyrinth, Gulliver's and Dibley's, and it is the one marketed for tunnel exploration. Australia's Coral Coast lists it with a maximum depth of about 30 m, deeper than the 12–18 m typical of the rest of the bay, which makes it better suited to Advanced divers.

The reef here is cut by tunnels and swim-throughs formed in the limestone, which attract glassfish and sweepers, and give shelter to crayfish, moray eels, wobbegongs and resting whitetip reef sharks. Outside the tunnels the reef supports the same fish-rich environment as the rest of the bay — schooling reef fish, turtles and sea snakes — with pelagic visitors possible along the deeper margins.

Detailed published accounts of the individual tunnels are scarce, so the dive is best done with an operator who knows the layout. Tunnels are short and open-ended rather than true overhead cave, but they still demand good buoyancy and awareness of other divers kicking up sand. Because it is less frequently scheduled than Blizzard Ridge, it is worth asking operators for it on calm days if you have Advanced certification.

Like the rest of Lighthouse Bay, it was affected by the 2025 marine heatwave; check with operators on current coral condition. Expect to spend most of the dive shallower than the maximum; the tunnels themselves are the focus and the deeper sections are optional for those with appropriate certification and gas.

Planning notes: Advanced Open Water certification is recommended and the site is rated intermediate. Expect to spend most of the dive around 15 m, with a maximum of about 30 m. Access is by boat only, and site selection depends on wind, swell and tide on the day. Best season: April–November (whale sharks March–July, humpbacks July–October, mantas year-round). Traffic: moderate (occasional charters/club dives).

What you might see

Glassfish and sweepers in tunnels, crayfish, moray eels, wobbegongs, whitetip reef sharks, turtles, sea snakes, schooling reef fish, occasional pelagics

Location

Reef with tunnels and swim-throughs in Lighthouse Bay off the northern tip of North West Cape; listed as the deepest of the Lighthouse Bay sites.

Facilities nearby

Bundegi boat ramp: toilets, shade, parking; air fills and hire at Exmouth dive shops