Nightly News | February 16, 2014
>>> as we've been reporti ining all throughout these winter games , the spring-like weather. back home in the states a staggering percentage of the great lakes is frozen over, the biggest freeze in decades. and along lake superior in northern wisconsin , it's giving visitors a rare and spectacular show of nature. our report tonight from nbc's john yang .
>> reporter: tens of thousands have made the pilgrimage here to the northern tip of wisconsin , trudging more than a mile across frozen lake superior , like penguins marching over polar ice . their quest? a rare view of majestic, natural cathedrals of ice. centuries of crashing waves created the caves. weeks of arctic blast , freezing falling water created the ice adorning them.
>> it's beautiful.
>> reporter: icicles hang like delicate chandeliers, accessible only for crawling. for photographers, the challenge is finding the perfect angle. for kids it's a giant frozen playground. molly oldman and peter johnson found it romantic.
>> we just got engaged.
>> reporter: the right spot for another kind of ice. in the summer months, you need a kayak to get in here. this spot of the lake is about 40 to 50 feet deep. but instead of all that water, i'm standing on at least 18" of ice. with 88% of the great lakes now covered by ice, it's the first time in five years the ice has been thick enough to walk to the caves.
>> over the last 30 years, there's been a huge decrease in ice cover and the length of the ice season on lake superior . this is a rare phenomenon and it's going to get rarer.
>> the last time and maybe there were 20 people the day we came. this cave, we felt like we owned it.
>> reporter: this time drawn by photos gone viral on the web, people are coming to the national park in record numbers, exploring on hands and knees, pulling children on sleds, even with dogs. the crowds are an unexpected boost for local businesses.
>> it's over the top , unbelievable. nothing we've ever seen before.
>> reporter: ice that put smiles on people's faces for a change with a dazzling display of nature's beauty. john yang , nbc news, national lake shore , wisconsin .
>> you just don't want to be under those things when it starts to warm up.