The Mary is a small historic wreck site in eastern Geographe Bay that most divers have never heard of. Marinelife.org.au describes her as a 65.6-foot wooden schooner built in 1868 that was wrecked on 4 June 1879 in heavy seas. She lies in shallow water about 40 m from shore, close to the piles of the old Lockeville Jetty, 2 km north-east of Wonnerup. The remains were relatively intact in the 1970s but are now mostly buried or dispersed, and may uncover intermittently as sand moves.

The jetty itself was part of the timber trade that once shipped jarrah from this coast, and its surviving piles offer some habitat for small fish in a largely sandy, seagrass-fringed bay. On most visits there will be little or nothing of the wreck to see, so the site is really for heritage enthusiasts and snorkellers exploring the quieter end of Geographe Bay.

It is extremely shallow and safe, with no need for scuba. The value of recording it here is historical: it is one of the few documented wrecks along the Busselton shoreline, and after big winter storms that move sand it may show more timbers. Like all wrecks over 75 years old it is protected, and nothing should be disturbed.

Combine a visit with the Wonnerup heritage precinct and the Busselton Jetty, and check recent weather: after a period of strong northerlies, sand movement may expose more of the hull. Bring only snorkel gear; scuba adds nothing here, and the water is rarely more than a couple of metres deep.

From Busselton drive east about 10-12 km toward Wonnerup, then continue along the coast road north-east to the Lockeville area. Park near the beach access closest to the old jetty piles and walk to the sand. The site is only about 40 m offshore beside the piles.

The nearest full-service dive shop for fills and hire is Swan Dive in Busselton; there is no dedicated dive shop in Margaret River or Augusta, so bring filled cylinders.

Very shallow site in sheltered eastern Geographe Bay; calm in most conditions except northerly winds. Sand movement determines whether any wreckage is exposed - the wreck uncovers only intermittently. General pattern in Geographe Bay: sheltered from south-westerly swell by Cape Naturaliste; summer mornings are calm before the afternoon sea breeze, while winter north-westerly fronts roll swell and chop into the bay and reduce visibility for several days.

Snorkel from the beach to the jetty piles and search the sand around them for exposed timbers. Snorkellers should stay within easy reach of the exit point and swim with a buddy; scuba divers at these depths need no safety stop but should ascend slowly and surface near the float.

No operator - self-guided snorkel. Nearest dive services: Swan Dive (Busselton/Port Geographe) for fills, hire, nitrox and charters; no dive shop in Margaret River or Augusta.