Lake Ontario is the only one of the Great Lakes that typically does not freeze over in the winter. Its relatively warmer water and the influence of the St. Lawrence River help maintain a temperature that prevents freezing. Additionally, its depth and size contribute to minimizing ice formation compared to the other Great Lakes.
In the center of the Lake is an Island. That is where the entrance is. During Winter the Lake will freeze and that is the only time you will be able to go there.
1979 was the last year that Lake Michigan froze over. Usually, ice only covers about 50% of the lake during the peak time in February. Actually, the lake did not completely freeze over in 1979 but it came pretty close. Also pretty close in 1977 and 1994 http://www.glerl.noaa.gov/pubs/brochures/ice/icecover.html
The Great Salt Lake in Utah is the only lake with the name "Great Salt Lake" but it is not the only saltwater lake in the world.
Lake Michigan
The Underground Lake is at the Bottom of the Winter Mine. The Winter Mine is only accessible during Winter. It is on an Island in the center of the Lake. In Winter the Lake freezes over and you'll be able to reach the Island.
Lake Michigain The only Great Lake that is completely in the United States is Lake Michigain.
Lake Michigan is the only Great Lake entirely within the US. The other 4 great lakes are on the border.
lake Michigan is the only great lake that does NOT touch Canada
Lake Michigan
Never. Lake Ontario has never frozen 'solid'. It may have frozen 'over' as in the entire surface. From Wiki " Lake Ontario will be at most one quarter ice-covered, in a mild winter almost completely unfrozen. Lake Ontario has completely frozen over on only two recorded occasions: during the winter of 1874-75, and in February 1934."
Lake Michigan is the only Great Lake that is not shared with Canada.
lake Michigan is found only in the USA