HMS Sirius is, as the Naval Historical Society puts it, Australia's equivalent of the Mayflower. She was the flagship of the First Fleet, leading eleven ships from England in 1787 to found the colony at Sydney Cove, and she was for a time the only link between the new settlements at Sydney and Norfolk Island and the outside world. Built as the merchant ship Berwick in 1780 at Rotherhithe, she was bought by the Royal Navy in 1781 after a fire, rebuilt, and rated at 511 tons with a gundeck of 110 ft 5 in (about 33.7 m) and ten guns.

On 19 March 1790, on a voyage carrying convicts, marines and children to Norfolk Island, Sirius struck the reef off Slaughter Bay while landing stores and was lost. Everyone survived, but the loss stranded the colony without its main supply vessel.

The wreck was declared a protected historic shipwreck in 1984 and added to the National and Commonwealth Heritage Lists in 2011. Archaeological work recovered three anchors and two carronades, which are displayed at the Norfolk Island Museum (the museum was established in 1988 with Bicentennial funding to display the Sirius artefacts); another anchor and a cannon stand at Macquarie Place in Sydney. Cosmos Archaeology's 2020 heritage management plan found the site relatively well preserved despite the surf, with most material still in place: mounds of cast-iron ballast pigs, anchor remains and flukes, a pump chamber, copper tacks and sheathing, musket balls and ceramics. Large sea urchin populations are a concern because they affect the iron.

For divers this is a historical pilgrimage rather than a scenic wreck. There is no hull; what remains is concrete-like ballast and fittings among the reef in a few metres of turbulent water. Conditions are the challenge: the site is diveable only on rare flat days. Look, photograph and leave everything exactly as found.

Norfolk Island is about 1,450 km east of Brisbane; flights run from Sydney and Brisbane (about 2.5 h; check the current carrier). A hire car is essential. The Sirius lies off Slaughter Bay at Kingston, about 10 minutes' drive from Burnt Pine.

Park on Bay Street or at Kingston Pier. The site is on the seaward edge of the reef in the surf zone, reached either by a long swim across the Slaughter Bay lagoon and over the reef crest on a flat day or by boat from Kingston Pier. Talk to Norfolk Island Diving and the Norfolk Island Museum before going.

See the recovered anchors, carronades and artefacts at the HMS Sirius Museum in Kingston.

The wreck site is in 'a rough and turbulent surf zone' on the outer edge of the Kingston reef, fully exposed to the prevailing south-east trades and to southerly swell. It can be visited only on rare days of flat calm with northerly or no wind and no southerly groundswell – typically in summer. Even a 1 m swell breaks on the reef crest.

Currents run out through the reef channels on a falling tide. Visibility is 10–30 m when calm. Plan around a high, slack tide for the crossing.

Only in flat calm, with local guidance. Cross the reef crest at the safest channel, then drift slowly over the seaward reef looking for ballast pigs, copper sheathing fragments and anchor remains wedged among the coral. Touch nothing, keep off the bottom and return before the tide turns.

Protected under the Underwater Cultural Heritage Act 2018; confirm with the Department (DCCEEW) whether any protected zone or permit applies before diving. No penetration – no hull remains.

No regular dive trips – visits only by arrangement with Norfolk Island Diving in rare flat-calm conditions; artefacts displayed at the Norfolk Island Museum (HMS Sirius Museum, Kingston).