as part of a father son road trip around SE New Mexico when I was in college. He was struggling with health problems that he thought were arthitus (but would be diagnosed a couple weeks later as bone cancer) but he gamely opted to do the full tour walking in at the natural entrance to the bottom and then taking the elevator out. It was the highlight of the trip and one of my fondest memories of him.

We didn’t have time to stay for the bat show in the evening – I’m told it is truly something to see. I will have to return and see it one day.