This week’s image comes to you from the Fairy Caves, now part of the Glenwood Caverns Adventure Park, just outside of Glenwood Springs, Colorado:
The Fairy Caves were originally discovered over 100 years ago, and promptly opened to tourism. Unfortunately, the original owners didn’t realize that the Caves were “living” caverns — still growing stalactites and stalagmites. So they blasted openings into the caverns without realizing that they had in the process dropped the humidity to the point where the caverns’ features could no longer grow.
Fortunately, people learned over time, and so airlocks were installed — and you can now walk through at least some of the caverns without impeding their natural growth.