The Centaur was a 188-ton, 30 m iron brig carrying galena (lead ore) from Dongara when she was wrecked on the Marmion Reef in 1874. She is now one of the historic features of Marmion Marine Park, and DBCA lists the wreck as a boat-access dive site at the southern end of the Marmion Reef line.

Little of the ship remains. The wreckage is scattered over about 30 m on the south-eastern section of the reef, heavily overgrown, and includes a section of the bow, hull plating, scattered galena and ship's fittings. A WA Museum plinth marks the site. The reef around the wreck is the attraction for many divers: in good conditions the site offers impressive shallow diving with swim-throughs through the limestone.

Reef life includes buffalo bream, wrasse, scalyfin, western blue devils, old wives and herring cale, with western rock lobster and Port Jackson sharks in the ledges and kelp and sponges on the reef.

The difficulty is that the wreck lies directly beneath a reef break. Divingwawrecks recommends diving only in swell under about 0.5 m, which in practice means a few calm mornings a year. On those days, it is a rewarding combination of history and reef.

The site suits Open Water divers with boat experience and an interest in maritime heritage. The wreck is protected, and nothing may be removed, including galena.

Water temperatures range from about 17 °C in late winter to 22–23 °C in late summer; a 7 mm suit with a hood is comfortable for most of the year.

Launch at Hillarys Boat Harbour (public ramps off Southside Drive) or the Ocean Reef boat ramp further north. The wreck lies at S 31°51.776' E 115°42.730' on the Marmion Reef system about 2 miles west of North Beach, a 10–15 minute run south from Hillarys. The wreck sits directly beneath a reef break, so approach carefully and anchor in sand clear of the breaking water.

A WA Museum plinth marks the site.

Marmion's reefs are exposed to south-westerly and westerly ocean swell and to the afternoon south-westerly sea breeze (the Fremantle Doctor), which in summer usually arrives between late morning and early afternoon. The wreck lies under a reef break and can be dived only when conditions allow: divingwawrecks suggests swell under 0.5 m. Any larger swell breaks over the site.

Dive early, before the sea breeze, after several days of easterly weather.

Anchor in sand clear of the break, descend and find the wreckage on the south-eastern section of the reef, including the bow section, hull plating and scattered galena. Then explore the reef's swim-throughs nearby before returning to the anchor.

Occasional club and private-boat dives in calm weather; DBCA lists it as a boat-access site.