Authorities in northern Michigan say it's no longer safe to visit spectacular ice caves that have formed along the Lake Michigan shoreline.
Milder temperatures and high winds have broken up the ice sheet on the lake side of the formations, and open water is visible near the caves. Large cracks have opened on some of the arches.
Thousands of people flocked to the area to see the caves last weekend, with lines of cars stretching more than 2 miles along narrow rural roads in Leelanau County, northwest of Traverse City.
A 21-year-old man was seriously injured Wednesday after falling 12 feet from one of the caves.