These are the sites few divers ever reach: Coral Sea seamounts, the Rowley Shoals, the far northern Great Barrier Reef, the Kimberley coast, Bass Strait islands and the offshore territories. Most are liveaboard or expedition access only, and the nearest recompression chamber is often a day away.
Ranked by distance offshore among sites recorded as remote or expedition-only, then by how rarely they are dived.
Updated daily from the directory. 30 sites listed.

1. Lord Howe Island · NSW
Offshore: 230 km · Remote southernmost coral reef with Galapagos sharks and black cod, and the hulk of the Runic on the reef flat.
2. Lord Howe Island · NSW
Offshore: 230 km · The fire-blackened hulk of a 13,500-ton ship, landmark of Middleton Reef since 1961.

3. Lord Howe Island · NSW
Offshore: 150 km · One of the world's southernmost coral reefs – huge numbers of Galapagos sharks and black cod in a rarely visited marine national park.

4. Coffs Harbour & Solitary Islands · NSW
Offshore: 27 km · Claimed to hold the densest population of anemones and clownfish on the Australian mainland coast, on the sheltered side of remote North Solitary Island.
5. Coffs Harbour & Solitary Islands · NSW
Offshore: 27 km · A novelty air-pocket cave where divers can briefly surface inside the rock, set within North Solitary Island's rich broader reef system.
6. Coffs Harbour & Solitary Islands · NSW
Offshore: 27 km · An easy, current-free swim-through cave surrounded by extraordinarily dense anemone beds and a 1980s trawler wreck, allowing unusually long bottom times of 75-80 minutes.

7. Coffs Harbour & Solitary Islands · NSW
Offshore: 27 km · A small point where an extraordinary density of fish concentrates in the current — one of the most photogenic schooling-fish spots in the Solitary Islands Marine Park when it is accessible.
8. Coffs Harbour & Solitary Islands · NSW
Offshore: 27 km · A remote, lightly dived grey nurse shark gutter system at North Solitary Island, offering quieter encounters than the busier South Solitary Island sites.
9. Coffs Harbour & Solitary Islands · NSW
Offshore: 27 km · A reef gutter named for the wedge-tailed shearwater (muttonbird) colony nesting on North Solitary Island above.
10. Coffs Harbour & Solitary Islands · NSW
Offshore: 27 km · An exceptionally fish-dense, easy patch of reef near Anemone Bay, valued for sheer density and variety rather than any single headline species.
11. Coffs Harbour & Solitary Islands · NSW
Offshore: 25 km · Massive boulder topography and a canyon-like channel between the island's two sections, with grey nurse sharks and giant groper — one of the park's best big-animal dives.

12. Shoalhaven Coast · NSW
Offshore: 16 km · Remote offshore banks with walls to 50 m, pristine colourful sessile life and pelagic sharks including hammerheads.
13. Port Stephens · NSW
Offshore: 14 km · A 1911 collier wreck at 42 m with an unusually well-preserved engine and boiler, and a strong resident mulloway and morwong population.

14. Port Stephens · NSW
Offshore: 11 km · A remote, fully exposed outer headland reef beneath a historic lighthouse, dived only in the calmest conditions.
15. Narooma & Montague Island · NSW
Offshore: 9 km · Fast drift over a boulder plateau east of the seal colony – experienced divers only.
16. Narooma & Montague Island · NSW
Offshore: 9 km · Deep sponge gardens and sea pens with plentiful fish at Montague Island.

17. Coffs Harbour & Solitary Islands · NSW
Offshore: 7.4 km · A remote, U-shaped pinnacle with a semi-trailer-sized tunnel through its base, huge jewfish and kingfish schools, and grey nurse sharks — one of NSW's great deep dive sites.
18. Sydney Northern Beaches · NSW
Offshore: 6.5 km · A canoe-ended barge, fully intact with its winches, whose hold fills with schools of jewfish – the furthest out of the Long Reef barges.
19. Ballina & Evans Head · NSW
Offshore: 6 km · A more distant, deeper offshore shoal north-east of Ballina, seeing very little diver traffic.

20. Central Coast · NSW
Offshore: 6 km · A remote deep wall 6 km south of Norah Head with a distinctive boulder formation (The Seven Apostles) and two secondary mini-walls.
21. Tweed & Byron Bay · NSW
Offshore: 6 km · Byron Bay's quiet offshore pinnacle system — good numbers of grey nurse sharks in winter with none of the diver traffic of Julian Rocks.

22. Sydney Northern Beaches · NSW
Offshore: 6 km · A 1919 collier with two big boilers, an upright stern and a shattered propeller, in the clearest water of any Sydney wreck.

23. Central Coast · NSW
Offshore: 5.8 km · A deep sixty-miler collier with an intact bow and some of the best fish life of any Central Coast wreck.
24. Sydney Northern Beaches · NSW
Offshore: 5.5 km · An intact 50 m MSB hopper barge on the Long Reef reef ground with an accessible bow void, in the clear water 3 nautical miles out.

25. Port Macquarie & Camden Haven · NSW
Offshore: 5 km · A scattered pinnacle and gutter system decorated with gorgonian fans, with both grey nurse and whaler sharks recorded.
26. Port Macquarie & Camden Haven · NSW
Offshore: 5 km · A pinnacle with a large basal cave and sponge garden supporting the rare eastern blue devil fish — one of the better macro dives in the Camden Haven offshore cluster.
27. Newcastle & Lake Macquarie · NSW
Offshore: 5 km · An upright, relatively intact 1908 tug with boiler, galley stove and side plating in place, alone on sand off Catherine Hill Bay.
28. Port Macquarie & Camden Haven · NSW
Offshore: 5 km · An unusual upside-down crane vessel wreck at 35-40 m, gradually being colonised by sponges and corals — a genuine insider's dive.

29. Sydney South & Botany Bay · NSW
Offshore: 5 km · An immense deep reef of walls, swim-throughs and sea-whip gardens 5 km off Cronulla, named for its wandering anemones.

30. Central Coast · NSW
Offshore: 5 km · A rarely dived deep technical wreck 5 km east of Norah Head, lost in a 1917 gale.
The guide
The list is ordered by distance from the coast among sites recorded as expedition-only or rarely dived, so it is a list of Coral Sea reefs and the atolls off the Kimberley. That is fair: these are the most remote reefs in Australian waters, days from a port and further from a recompression chamber. But remoteness is not only distance. Bass Strait islands, the far south coast of Tasmania, the Great Australian Bight and the Nullarbor caves are remote in every practical sense and sit lower down only because they are near land.
Read the list alongside the under-the-radar ranking, which finds the quiet sites close to home, and the liveaboard category, which is how most divers actually reach the outer reefs.
The Cairns liveaboards run Osprey, Bougainville and Holmes reefs on three- to seven-night trips year-round, with the settled season from September to December. The reefs at the top of this list (Mellish, Lihou, Cato, Marion, Wreck Reef) need an expedition charter of ten days or more, typically out of Cairns, Gladstone or Bundaberg, and they are offered irregularly. Ask the Coral Sea operators about their long-range schedule a year ahead.
For the Rowley Shoals and Scott Reef, boats leave Broome from late September to November. Ashmore Reef is a Commonwealth reserve with permit access and no commercial diving. The Kimberley cruises visit the inshore reefs and the Lacepede Islands rather than the outer atolls.
The nearest chamber to the outer Coral Sea is Townsville, often more than 24 hours away by sea and aeromedical evacuation. Boats carry oxygen, and the good ones brief conservative profiles: no decompression, 30 m limits, long surface intervals, and no diving on the last day before a long steam. Diving insurance with evacuation cover (DAN or equivalent) is a booking condition on most vessels, and it should be. The safety guide covers what evacuation from remote Australia actually involves.
Editorial last reviewed September 2026. The list itself is regenerated from the directory daily.
Almost all need a liveaboard or expedition charter: Coral Sea boats from Cairns (September–December), Rowley Shoals boats from Broome (October–November), far northern reef expeditions in October–November, and Kimberley cruises in the dry season. Book months ahead and carry DAN cover.
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