Sightseers trek across a frozen expanse of Lake Superior, the world's largest freshwater lake, to the sea caves of the Apostle Islands National Lakeshore near Cornucopia, Wisconsin February 15, 2014. ... more 
Sightseers trek across a frozen expanse of Lake Superior, the world's largest freshwater lake, to the sea caves of the Apostle Islands National Lakeshore near Cornucopia, Wisconsin February 15, 2014. REUTERS/Eric Miller less 
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Reuters | Photo By ERIC MILLER / Reuters
Sun, Feb 16, 2014 2:59 PM EST