They don't mention anything about an upper age limit, but you need to be somewhat fit and sure footed. We were on the 90 minute Family tour and there was a woman there with her 80 year old mother...she managed the hike up to the cave entrance but when she got inside she had second thoughts about the decent into the cave. I believe the 3 hour tour is much more physically challenging.
There are some stretching spots and some making yourself small spots and I was surprised that they didn't ask us any questions about our fitness level prior to the experience. At the end, I asked the excellent guide who said pretty well everybody could find a way around. But I felt it was challenging(I am a 55 year old not terribly fit, not terribly fat, just average person).
It was lots of fun and I would recommend it.
You just need to be fairly mobile and in fairly good shape.
I don't think there is a defined upper age limit but more capability to maneuver in tight areas and keep up with the group. Hope it helps
The category only says 'adult'. As long as a person is agile and can hike 20 minutes of switchbacks, they'll have a blast.
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