Lake Ontario is the smallest of the five Great Lakes of North America, located between the Canadian province of Ontario and New York state.
One Canadian alternative to the traditional Triple Crown of Open Water Swimming* is the 51K traditional route from Niagara-on-the-Lake to Toronto's Marilyn Bell Park in Lake Ontario.
A total of 51 swimmers have made it to date including a number of open water heroes like Marilyn Bell (the first to cross), Diana Nyad, John Kinsella, Cindy Nicolas and Vicki Keith (who did the only double crossing in 56 hours). Authorative descriptions of these grand swims are posted at Solo Swims of Ontario.
The challenge is the water temperature that can dramatically fluctuate overnight and even on the same swim.
* The traditional Triple Crown includes the English Channel, the Catalina Channel and the Manhattan Island Marathon Swim.