Centuries of wave action, freezing and thawing have sculpted shorelines throughout Apostle Islands National Lakeshore in Wisconsin. People come to "The Jewels of Lake Superior" in summer and winter to visit the sea caves and witness Lake Superior's ever-changing handiwork. In summer, the red sandstone is sandwiched between a sapphire blue lake and emerald green forests that grow right up to the brink of the cliffs. Under calm conditions, kayakers can explore the caves' deepest recesses while listening to the sounds of the largest of the Great Lakes. Photo by Michael DeWitt ALT TEXT: A view through a sandstone arch out onto a sunrise over Lake Superior