Upsala Glacier, Snow-capped Mountains, Glacial Lake, Los Glaciares National Park, Patagonia, Argentina

A crumbling giant

This sweeping tendril of frosty blue looks impossibly large on its own, but it's just one exit glacier of the enormous Northern Patagonian Ice Field—one of the world's biggest masses of ice. At the point where it meets San Rafael Lake, huge icebergs often crumble off the glacier's edge into the tidal waters below, which connect to the Pacific Ocean via a series of channels and fjords. The thunderous spectacle is popular with tourists, who flock to cruise boats and kayak tours for a closer look at the calving action.