Other Great Lakes
(In general, trial swims are 1/3 of the distance of the intended big swim, rounded up to the next kilometer).
Lake Huron is over 300 km long (north to south) but the east west width is at least 70 km except at the southern tip. This clear blue lake is quite warm In August but the waves can get quite high.
Traditionally, the Lake Huron swim has been the 55 km stretch at the southern end of the lake from Port Sanilac, Michigan to Port Franks, Ontario. There has been one 75 km crossing from Harbor Beach, Michigan to Goderich, Ontario.
The route from Tobermory, at the tip of the Bruce Peninsula, to South Baymouth, at the tip of Manitoulin Island, is very cold and treacherous. This route parallels the route of the Chi Cheemaun Ferry and is full of unpredictable currents swirling between Lake Huron and Georgian Bay.
Lake Huron - Georgian Bay
Georgian Bay could be a Great Lake unto itself but in fact it is a shallower and warmer bay of Lake Huron. It has numerous islands and many rocky points and peninsulas offering many different routes of 16 - 30 km, although a true east west crossing would be over 50 km.
Two examples of routes are the swim from Collingwood to Christian Island and the crossing of Severn Sound.
Lake Superior is by far the greatest of the Great Lakes. The distances, winds, waves, and weather are extreme. The water temperature rarely goes above 15°C. The ports and available boats are few and far between.
There are two routes, a 32 km route at the western end, near Duluth that is between Minnesota and Wisconsin, and a 29 km route at the eastern end between Whitefish Point, Michigan and Pancake Bay, Ontario.