I turned 65 on these hills. It was a blast. I feel it is a tough climb for many .. It just depends on her energy level. If she can walk 2 flights of stairs without being too winded then she's set. (I am a PT as well).
I asked the tour guide about this and she say there was an 96 year old lady did the zip line. There's a total of 5 zip line and the first 4 is a relatively simple hike. The last one is a 15min (give or take) hike. And the guide that I ask, say the 96 year old lady did the first 4 and didn't do the last one. I assume you need to let the place know beforehand and it shouldn't be a problem. But to make sure, you should call beforehand to make sure.
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