BAYFIELD, Wis. — Stalactites point downward like frozen daggers, water molecules morphed into icicles taller than two-story houses.
It happens every year along the shores of Lake Superior near Bayfield, but few have seen the spectacular ice caves in the Apostle Islands National Lakeshore in many years.
For the first time since 2009, ice along the shore is solid enough to support hardy visitors willing to hike more than 2 miles round trip to ogle the natural sculptures. When word recently filtered out that the caves were open once again, thousands trekked out to see them with 2,000 visitors last week Saturday and another 2,000 on Sunday — possibly the busiest weekend the park has ever seen.
No one is sure how long the glacial art gallery will remain open.
“We tell people you can’t predict how long this will last,” said Bob Krumenaker, Apostle Islands National Lakeshore superintendent. “Obviously this is an early season and signs are showing that the ice on Lake Superior is growing. It might last several weeks or one really big wind storm will break it up.”
Numerous indentations in the 1-billion-year-old Cambrian Era sandstone have created caves where kayakers sometimes paddle in during the summer. They’re not large caves. The National Park Service and the caving community define a cave as anything that’s at least 50 feet deep.
Water from several streams that flow along the bluffs as well as surface and groundwater have created exquisitely beautiful ice sculptures. Icicles are formed from waves blown against the rocks while temperatures are below freezing. Meanwhile, very delicate crystal-like formations are birthed by humidity colliding with cold air.
“One of the interesting things is as long as it remains this cold, there will be growth of those kind of features. Once we get some melting, the formations melt a little bit and reform,” Krumenaker said. “They’re still spectacular but not as delicate.”
The mainland caves in the 21-island park are located 18 miles west of Bayfield.
This week one of the caves was totally encased in ice, like bars on an iceberg jail. Ice formations varied in color from bright white to yellow to golden, making the caves look like giant geodes filled with sparkling quartz.
Walking out to the caves can be arduous depending on weather and conditions of the shoreline, which can range from uneven ice to hip-deep snow.
While skis probably wouldn’t work, snowshoes could make some of the travel easier as would ski poles or a hiking stick. Snowmobiles are not allowed out to the caves.
It’s not for the faint of heart.
“It’s not uncommon to be out there and hear the ice crack. It’s almost like it’s a living organism,” Krumenaker said. “It’s complicated and fascinating.”
Conditions can change quickly. Last February, park staff planned to open the caves to visitors and were meeting one last time when the phone rang in Krumenaker’s office.
It was a staff member who had just checked a wave camera and noticed the ice had broken up overnight. Plans to open the caves were called off.
Normally in the winter only a handful of visitors come to the park. Because of budget cuts the Apostle Islands National Lakeshore visitors center is closed though people can stop and pick up brochures.