HMS Pandora is one of the most historically significant shipwrecks in the southern hemisphere. The Royal Navy frigate, with a crew of 135, was sent to the South Pacific in 1790 to hunt down the mutineers of HMS Bounty. Having captured 14 of them in Tahiti, Pandora was searching for a passage through the Great Barrier Reef when, according to the Queensland Museum, she struck the reef around 7:20 pm on 25 August 1791 in fading light.

The crew managed to refloat her, but the hull was badly damaged; during the night a pump broke down and the water gained. She sank the next morning with the loss of 35 lives – 31 crew and four prisoners – while 99 survived (89 crew and 10 prisoners) and made an epic open-boat voyage to Timor. The wreck lies within Pandora Entrance, about 5 km north-west of Moulter Cay and roughly 140 km east of Cape York, on a sandy seafloor in about 30 m of water behind a coral outcrop (Mike Ball gives 33 m).

Discovered in 1977, it was the subject of nine Queensland Museum archaeological expeditions between 1979 and 1999, which recovered more than 7,500 artefacts now displayed at the Museum of Tropical Queensland in Townsville. A substantial part of the hull survives, buried in sand. Divers who visit on Mike Ball's southbound expedition see the anchor and stove remains and exposed timbers on a white sandy bottom; Divernet reports visibility of around 40 m on a good day.

The wreck is protected under the Underwater Cultural Heritage Act 2018, with a 500 m protected zone that requires a permit to enter and dive, and aerial surveillance patrols. This is a deep, short dive with a strict hands-off rule. It suits experienced divers with deep certification who value history over marine life, though the surrounding reef is also rich.

Few people will ever dive it; those who do are visiting one of the key sites of Australian maritime archaeology.

Liveaboard only – there are no day boats, resorts or public moorings this far north. Mike Ball Dive Expeditions' Spoilsport runs 7-night 'Northern Exposure' expeditions between Cairns (Trinity Wharf) and Horn Island in the Torres Strait each November (northbound and southbound, up to 27 dives), plus a 7-night Far North Coral Sea Exploratory round trip from Cairns in October. Spirit of Freedom runs 7-night far-north expeditions from Cairns in October–December, and Professional Dive Services' MV Kalinda has run longer (13-night) Cairns–Horn Island trips.

Horn Island has daily scheduled flights to Cairns (book separately; allow 24 hours after diving before flying). The far-northern reefs are roughly 500–650 km north of Cairns – one to two days' steaming each way.

The far-northern reefs are only diveable in a narrow weather window. The south-east trades blow hard from about April to September and make the long open-water passage and the exposed outer walls impractical, so expeditions run in the transition period, typically October–December, when winds are lighter; the northerly monsoon, storms and cyclones (December–April) close the season. Even in the window, exposed shelf-edge walls (Tijou, Great Detached, Raine) need calm days, and skippers switch between reefs to find shelter.

Strong tidal currents and upwellings run along the continental shelf and through reef openings – channel sites are timed to slack water. Visibility varies from about 12 m to 40 m+ depending on tides and any rain. Marine stingers are present from November.

Under permit only, following the operator's plan: descend a shot line to the sand at about 30–33 m, remain outside the wreck without touching anything, view the anchor and stove remains and the exposed hull, then ascend the line with a slow ascent and extended safety stop.

Depth 30–33 m: nitrox EANx28–30 with MOD checked is ideal; bottom time is short (about 15–20 minutes on air within NDLs); use a shot line and plan an extended safety stop.

Mike Ball Dive Expeditions (Spoilsport) – included on the 7-night Northern Exposure southbound (Horn Island–Cairns) expedition in November, under the operator's permit; otherwise access only with a permit from the Australian Government (Underwater Cultural Heritage Act 2018).