Diving Through Maritime History – Four Historic Shipwrecks in Gulf St Vincent
| Activity | Scuba Diving (Intermediate) |
| Distance | 115 kilometres (across multiple dive sites) |
| Duration | 1 day minimum (multiple dives across sites) |
| Region | Adelaide & Adelaide Hills / Fleurieu Peninsula / Yorke Peninsula |
| Accommodation | Camping, mid-range and premium options — see Adelaide Hills, Fleurieu Peninsula and Yorke Peninsula accommodation |
| Start Point | Port Willunga (Star of Greece wreck) |
| End Point | Ardrossan (Zanoni wreck) |
| Permit Required | Yes – Heritage SA permit required for Zanoni dive site |
| Certification Required | Open Water dive certification minimum |
Overview
Beneath the calm blue waters of Gulf St Vincent, stretched across 115 kilometres of South Australian coastline, lie the remains of four ships that helped build a colony. Adelaide’s Underwater Heritage Trail connects the wrecks of the Star of Greece, the Grecian, the Norma, and the Zanoni — each one a vessel that came to grief in the waters off Adelaide during the 19th and early 20th centuries, and each one now serving as both a protected heritage site and a thriving artificial reef teeming with marine life.
This is not a single trail in the conventional sense, but rather a collection of four dive sites scattered between Port Willunga on the Fleurieu Peninsula and Ardrossan on Yorke Peninsula. Underwater plaques have been installed adjacent to each wreck, providing historical context for divers as they explore the remains. Together, the four wrecks tell a story of South Australia’s maritime past — of trade, ambition, and the unforgiving power of the Southern Ocean.
The Wrecks
Star of Greece – Port Willunga
The Star of Greece is perhaps the most dramatically situated of the four wrecks. She was an iron-hulled barque that ran aground at Port Willunga in 1888 during a sudden gale, with the loss of 18 lives. Today, her remains lie in shallow water off the beach, visible at low tide as rusted ribs and hull plates emerging from the sand. The site is completely exposed to the open ocean, so diving conditions must be near-perfect — ideally several calm days in a row before attempting the dive. When conditions align, the wreck is easily accessible and surrounded by schools of fish that have colonised the iron structure.
The Grecian
The Grecian adds another chapter to the story of maritime misfortune in Gulf St Vincent. Like her companion wrecks, the Grecian has become an artificial reef, her degraded structure providing habitat for a diverse community of marine organisms. Divers can explore the remaining structure while reading the underwater heritage plaque that describes the vessel’s history and the circumstances of her loss.
The Norma – Outer Harbour
The Norma was a steel four-masted iron barque of 2,122 tons, measuring 278 feet in length. She sank in the main shipping channel of Outer Harbour in 1907 after being rammed while at anchor by the vessel Ardencraig. Today, the wreck lies approximately 5 kilometres offshore from North Haven in 14 metres of water. The dive site is subject to strong tidal currents, making it suitable for experienced divers. The bow area remains recognisable and acts as a marine haven — fish life is prolific, and wobbegong sharks are frequently encountered resting among the wreckage.
The Zanoni – Ardrossan
The Zanoni, built in 1865 and sunk in 1867, is the oldest of the four wrecks and the most strictly protected. The wreck lies within a protected zone administered by Heritage SA, and divers require a permit before visiting the site. A boat mooring buoy has been installed to prevent anchor damage, and it is illegal to damage or interfere with the wreck — penalties include substantial fines, imprisonment, and confiscation of equipment. For permitted divers, the Zanoni offers a rare chance to explore a remarkably well-preserved 19th-century vessel in a controlled heritage environment.
Heritage Protection
South Australia has been a leader in the protection of underwater cultural heritage. The Underwater Cultural Heritage Act provides comprehensive coverage for shipwrecks, submerged aircraft, and other types of underwater cultural heritage, along with the fragile marine environments that surround them. The four wrecks on this trail represent a variety of vessel types associated with trade and development in colonial South Australia, and their protection ensures that future generations of divers can experience these sites.
Planning Your Dives
Diving the full trail requires planning, as the sites are spread across more than 100 kilometres of coastline. Most divers tackle the wrecks over multiple trips rather than in a single day. A minimum Open Water dive certification is required, and experience with current diving is recommended for the Norma site. Several Adelaide-based dive operators offer guided tours to the wreck sites, which is an excellent option for visiting divers or those unfamiliar with local conditions. A 7mm or semi-dry wetsuit is recommended for year-round comfort, and summer offers the calmest conditions for the more exposed sites like the Star of Greece.
Adelaide’s Underwater Heritage Trail offers something no land-based walk can match: the chance to descend beneath the surface and touch the physical remains of South Australia’s maritime history. Each wreck is a time capsule, a reef, and a memorial — a place where history and marine ecology converge in the cool, clear waters of Gulf St Vincent.
Where to Stay
Planning an overnight trip? See our Adelaide Hills Accommodation Guide for the best places to stay near this trail.