Canada has rarely been claimed as the location of Atlantis. In fact the only reference, that I was initially aware of, was by Samuel Poe in a truly dreadful book, in which he claimed that the east coast of Canada and United States had been Atlantean.
Then, Brian Johnston, a retailer of precious stones, created a website(a) advocating Ontario as the location of Plato’s Atlantis. He offers a stone circle and what may be other megalithic standing stones along with many photos of the same as evidence. This is all held together by a large helping of speculation. Finally, after describing in some detail a site in Ontario’s Northumberland County, he concludes that the location “might not be Atlantis!”
*Nevertheless, the idea that the ancient Greeks had an awareness of America has persisted, with some claiming that they had colonies in Canada. Among these are Lucio Russo, Ioannis Liritzis(b) and Minas Tsikritsis. Now Manolis Koutlis has gone one further and claims that not only were there Greek colonies in Canada, but that Atlantis had been situated in the Gulf of St. Lawrence.*