We have passed this monument on other trips and I always wanted to go back and am glad I did. At first I was a little intimidated by the sample stairs that they ask you to climb up and down without holding the rail which I could do but when someone said something about hundreds of stairs, I wasn't so sure because I'm 66. After another visitor said there was an opportunity to get out about 1/3 of the way through, I felt I had an out if it was too hard. I was easily able to keep going at 1/3 mark and finished the tour just fine. You are not supposed to touch the rocks and edges of the cave to avoid contaminating it, and the really steep places have stairs with rails you can use for support. I found I could manage OK except in one or two awkward areas where I had to lightly touch a rock for balance. If you are somewhat active and use stairs regularly, you should be OK. It's and interesting and informative excursion about cave ecology and geology but the best part in my opinion was getting out of the cave and taking the .7 mile trail to the top of the mountain afterwards where there's a nice bench to sit on and enjoy fabulous views of the mountains.