About 150, 000 years ago, the area that is now known as Monroe County in southwest Illinois was covered in ice hundreds of feet thick. When the ice melted, the water flowed into fractures in the area’s limestone bedrock....
Visitors can once again don hard hats and wade through an underground stream to explore the cave’s geological treasures.“ It’s such a unique experience that no other place offers in Illinois, ” said Mic Middleton, the site supervisor for the natural resources department....
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芝加哥论坛报-芝加哥突发新闻
2021-07-21 00:00:00.0