Scenes from the Apostle Islands National Lakeshore in Bayfield, Wis., where Lake Superior's ice is thick enough to walk to the area's sea caves for the first time in five years.
Derek Montgomery for MPR News
This winter's intense cold has brought a fringe benefit to people who live around southern Lake Superior: They can walk to the uniquely beautiful, and currently frozen, sea caves of the Apostle Islands. It's the first time the lake's ice in that area has been thick enough to walk on since 2009.
Thousands of people have been walking out to the caves, as we learned from our friends at Minnesota Public Radio last month. And today, MPR is featuring images of mammoth icicles and frosted rock formations, in photos taken Tuesday.
The sea caves are part of the Apostle Islands National Lakeshore in Bayfield, Wis., an area close to Minnesota. Neil Howk, the assistant chief of interpretation at the park, told MPR last month that they represent a "spectacular" part of the area's geological history.
"The sea caves have been forming over the last 10,000 years or so, since the last great continental ice sheet melted," Howk said. "We get thousands of people coming here — usually in the summertime, to go out and look at the caves by kayak and by boat.
"But right now, that beautiful layer-cake geology of sandstone is all covered up with this incredible frosting of ice. And it makes them almost otherworldly."
Howk told MPR News Morning Edition host Cathy Wurzer that the Apostle Islands had averaged nearly 1,000 visitors a day in the first 10 days the caves were open.
It's a scenic — and bitingly cold — winter along the Great Lakes. As Mark reported last week, the frigid conditions created a photo op at Lake Michigan, where a satellite image captured a striking view of the partially frozen lake.