It is a popular winter attraction – the Bayfield Ice Caves. The caves were formed millions of years ago by the action of glaciers and waves that sculpted the sandstone into amazing cliffs towering over Lake Superior. During summer, the caves are inaccessible and can be viewed only from the water. But when the lake freezes in the winter, visitors can walk over the frozen lake surface and access one of northern Wisconsin’s most stunning natural formations. Inside the caves, the water dripping from the ceiling freezes into thousands of icicles, while the entrances become framed by frozen waterfalls that extend to the top of the cliff.