Hikers make rare visit to ice caves of Lake Superior

Lake Superior's ice caves offer glimpse of nature's fleeting beauty 02:20

CORNUCOPIA, Wis. -- Each step is a challenge for the thousands making the mile-long hike across ice to an isolated stretch of coastline on Lake Superior.

The reward: Caves seem to be covered in crystal and icicles dangle from cliffs two stories high.

"It's just fantastic," says Jim McLaughlin, of Hayward, Wis. "It's a lot better than we thought it would be."

The one-billion-year-old sandstone is full of cracks. Lake water seeped in and froze on the walls and ceilings. James Fuchs has come twice from Shoreview, Minn.

"It's unique to see water in so many different forms and different colors and the way it's sculpted," he says. "It's just incredible. You couldn't dream this up. You couldn’t have a mind's eye to almost create this. You have to come and see it."

Winter access to the caves is only possible when the ice is thick enough to safely walk on. Conditions haven’t been right for this to happen in five years, and some fear the unusual event could become even rarer.

Thousands have hiked across ice to an isolated stretch of coastline on Lake Superior. CBS News

Although it's been a brutal winter, a study of the Great Lakes ice pack found that over 30 years, it decreased by 70 percent. Park Superintendent Bob Krumenaker points to climate change.

Lake Superior's dazzling ice caves 14 photos

"We are referring to the ice cave experience as a truly endangered national park experience, because, like endangered animals, we can't predict its future, and it may not be there," Krumenaker says.

But for those lucky enough to enjoy this year's show, it's a moment frozen in time.

"It's in my mind," Fuchs says. "I won't forget this, it's too special."

A spectacle that ends when winter finally begins its surrender to spring.

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