Visitors showed up by the thousands over the weekend to see ice caves nestled into the shoreline of northern Wisconsin.
The Apostle Islands National Lakeshore ice caves are located several miles outside of Bayfield, Wis., on a 12-mile stretch along the coast. In order to see the caves, Lake Superior has to freeze enough for spectators to walk over ice to the caves.
The ice was thick enough for the caves to open on Saturday, attracting nearly 12,000 people over the weekend, according to Julie Van Stappen, Chief of Planning & Resource Management at the Apostle Islands National Lakeshore.
Park officials had checked ice conditions Wednesday to make sure the ice was almost a foot thick to hane the foot traffic.
In the past few months strong winds broke up the ice cover and prevented the caves from opening, according to Neil Howk, assistant chief of interpretation and education for the Apostle Islands National Lakeshore.
Howk says he's unsure how long the caves will be accessible, which is dependent on the weather. This year park officials warned visitors to wear ice cleats on their shoes and bring ski poles.
"The ice is barren so it's like walking on a hockey rink. It's incredibly treacherous," Howk said.
The ice caves were accessible for 10 weeks last year, and 15,000 people visited the caves on the busiest day, according to Howk.
In 2014, the park had to dip into emergency funds to deal with the huge crowds so this year the park is charging a $5 admission fee for visitors 16 and older, according to Van Stappen. The fee doesn't seem to be deterring visitors.
On Sunday there was a line of cars 2½ miles long parked to see the islands, according to a post on the Apostle Islands National Lakeshore Facebook page.
In the past 20 years the park has seen the effects of climate change first-hand making it harder for people to see the caves.
"The opportunity to visit the ice caves has come less and less often," Howk says. Before last winter it had been 2009 since there was enough ice for people to get to the caves, he says.
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