This unusually cold weather is making the ice thicker on parts of Lake Superior, and that's providing the opportunity to explore one of our region's most beautiful hidden winter gems. The sea caves of the Apostle Islands are accessible by foot for the first time since 2009.

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If you've seen any of the photos of the caves posted around the Internet these last few days, you'll know that they are home to some stunning ice formations right now. We've posted a few here from freelance photographer Bryan Hansel.

Neil Howk, the assistant chief of interpretation at the Apostle Islands National Lakeshore in Bayfield, Wis., spoke with MPR News Morning Edition host Cathy Wurzer about the ice caves. Click the audio player above to hear their conversation.