Rottnest has more than a dozen recorded shipwrecks, and the WA Museum and Rottnest Island Authority have turned them into a heritage trail that works on land, on the surface and underwater. Plaques were placed both beside the wrecks and on shore, and underwater plinths mark the Transit, Gem, Raven and others. The Museum's trail guide covers the Transit (1842), Gem (1876), Lady Elizabeth (1878), Macedon (1883), Mira Flores (1886), Janet (1887), Denton Holme (1890), Raven (1891), City of York (1899), Shark (1939) and Uribes (1942); Wikipedia's list adds the Ulidia (1893, on Stragglers Reef), the yacht Anitra II (1979, Cape Vlamingh) and the Kiryo Maru I (1984).

The land trail starts at the museum and leads to an overlook with the areas where the Macedon, Denton Holme, Janet, Transit and Gem were lost, and anchors from the Mira Flores and City of York, before continuing to Bathurst Point Lighthouse and the Leeman monument. For swimmers, the Museum recommends only two wrecks as snorkel dives: the sand-filled Uribes at the Natural Jetty and the Shark barge at Henrietta Rocks, both metres from shore and only in calm seas. The Thomson Bay wrecks are visited by glass-bottomed and semi-submersible tour boats and are the easiest scuba wrecks.

The trail is a good framework for a Rottnest holiday: it links the island's history of reefs, lighthouses and pilots with sites for every level from non-swimmer to Advanced diver. All the wrecks are protected under Commonwealth and State maritime archaeology legislation. Maps are available from the Visitor Centre.

Catch the ferry from Fremantle, Perth or Hillarys to Thomson Bay and collect a trail map at the Visitor Centre. The land trail starts at the Rottnest museum and runs to an overlook with views over the Transit Reef wreck sites and the Mira Flores and City of York anchors, then on to Bathurst Lighthouse. Cycle or use the Island Explorer bus to the plaques around the island: Uribes near Stop 4 and the Shark at Henrietta Rocks (Stop 3) are the two snorkel stops.

The offshore wrecks need a boat or dive charter from Fremantle.

Choose the side of the island in the lee: north-coast wrecks (Macedon, Denton Holme, Janet, City of York, Mira Flores) in southerly and easterly winds; south-coast sites (Shark, Lady Elizabeth) in northerly and north-easterly winds. The Museum stresses that Uribes and Shark should only be snorkelled in calm conditions. General pattern at Rottnest: summer brings calm morning easterlies followed by a strong south-westerly sea breeze from late morning, so dive early; winter brings north-westerly fronts and large swell, with clear, calm spells between them.

Check the Bureau of Meteorology coastal forecast for swell height and period before committing.

Do the land trail and plaques by bike in the morning, snorkel Uribes and the Shark in whichever lee is calm, and book a charter for the Macedon/Denton Holme on another day. Agree a turn pressure before descending (half gas, or a third where current is likely), carry a DSMB, and make a 3-minute safety stop at 5 m.

Self-guided; glass-bottom and semi-submersible tours visit the Thomson Bay wrecks; Perth Scuba, Bucket List Diver and Dolphin Scuba dive the boat-access wrecks on Rottnest day trips.