Shipwrecks are another of the Great Lakes’ mysteries. There are 5,000 recorded wrecks and an estimated 5,000 or so that didn’t warrant recording – that’s one wreck for every mile of coastline. In Tobermory, Ontario, the last significant wreck happened close to a century ago, and it joined a long list of others that sank in these waters before it.  This piece of coastline has had more than its share of casualties because of the jagged limestone rock formations and the prevalence of strong winds which drive ships towards the shoals - bad news for the poor sailors who had the misfortune of being in the wrong place at the wrong time, but good news for the divers who come here by the thousands to explore the remains.  The waters near Tobermory have been designated a National Marine Conservation Area called Fathom Five National Marine Park , so these wrecks will be preserved for a long time to come.