Ranked by recorded summer water temperature: the Top End, the Kimberley, the far northern reef and the Indian Ocean territories, where 30 °C water is normal and a 3 mm suit is for sun protection.
Updated daily from the directory. 25 sites listed.

1. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · An 18–20 m trepang vessel lying on her port side with wheelhouse, rails and a large Kort nozzle clearly visible and good coral growth.

2. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · A 25 m prawn trawler cleaned by Darwin Sub Aqua Club volunteers and scuttled in 2013 – upright, open and busy with snapper and jewfish.

3. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · Upright 22 m coastal trader scuttled in 2011 with a steel barge alongside – part of the Antares, Amelia C and Merindah Pearl wreck cluster.

4. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · An improvised early-1990s reef of steel pontoons, truck tyres, concrete bus shelters and a 10 m boat, known for very large cod.

5. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · The 32 m ex-research vessel and prawn trawler that founded the Fenton Patches reef field in 1988 – upright, intact and heavily fish-populated around the stern and rudder.

6. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · A 25 m ex-pearling vessel prepared by DSAC volunteers and scuttled in 2013 at the northern end of the Fenton wreck cluster.

7. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · About 200 tonnes of large concrete pipes forming tunnels and overhangs that shelter big cod and jewfish.

8. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · An old Coca-Cola bottle-washing machine surrounded by 1,500 tonnes of concrete culverts – a shallow, fishy and unmistakably Darwin reef.

9. Tiwi Islands · NT
Summer water: 30-32 °C · A 1942 blockade-runner sunk in the first Darwin raid, found in 2008 – intact stern on its side in 16 m and a shattered ammunition-laden bow, in a closed protected zone.

10. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · Plant equipment, 1,500 tonnes of concrete culverts and five shipping containers in 15 m, with the Van Bruggen yacht wreck nearby.
11. East Arnhem Land & Gove · NT
Summer water: 30-32 °C · A 1937 Japanese pearling mother-ship in 26 m off Arnhem Land – archaeologically significant and inside a closed 200 ha protected zone.

12. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · The NT's largest surviving colonial wreck: an 85 m 1881 steamer whose boilers break the surface at low springs while the intact stern lies in 12 m.

13. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · Twenty mining road-train side tippers and two steel vessels in 15 m – with the Kay Lee wreck and its giant groper close by.

14. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · Coral reefs rising steeply from fast tidal channels in Clarence Strait, with Spanish mackerel feeding along the edges – the best natural reef within reach of Darwin.
15. Darwin Offshore & Artificial Reefs · NT
Summer water: 30-32 °C · Tidal blue holes that become sheltered, fish-filled coral pools at low tide – with a 'horizontal waterfall' as the water drains out.

16. Darwin Harbour · NT
Summer water: 29-32 °C · A small, upright refugee boat packed with fish, in reach of two other wrecks on the same dive.

17. Darwin Harbour · NT
Summer water: 29-32 °C · An upturned construction barge whose cylinders and beams form a maze of overhangs full of fish.

18. Darwin Harbour · NT
Summer water: 29-32 °C · A modern confiscated fishing boat lying intact on its side, with holds and wheelhouse visible - the shallowest of the complex.

19. Darwin Harbour · NT
Summer water: 29-32 °C · Upright, intact Cyclone Tracy trawler in 12 m with some of the harbour's best fish life - Darwin's best beginner wreck.

20. Darwin Harbour · NT
Summer water: 29-32 °C · An upright 40 m steel refugee boat with open holds, good coral and strong fish life, beside two other wrecks.

21. Darwin Harbour · NT
Summer water: 29-32 °C · An American freighter sunk in the same raid, upright in 20 m with cargo still in the holds.

22. Darwin Harbour · NT
Summer water: 29-32 °C · The former Huddart Parker liner and troopship, now the most coral-covered of the 1942 raid wrecks.

23. Darwin Harbour · NT
Summer water: 29-32 °C · A 130 m US Army transport sunk in the 1942 air raid, the largest and most-dived wreck in Darwin Harbour.

24. Darwin Harbour · NT
Summer water: 29-32 °C · An upturned Cyclone Tracy trawler draped in gorgonians, a few minutes from the CBD and sheltered from the trade winds.

25. Darwin Harbour · NT
Summer water: 29-32 °C · An almost intact RAAF Dakota transport that ditched off Mindil Beach in 1946, reached by a heritage mooring and guide line.
Darwin Harbour and the Top End reach 29–32 °C in the wet season, with the Kimberley, Torres Strait, Christmas Island and Cocos close behind at 27–30 °C.
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