Does it count that my daughter went? She was in very good shape and still found there was a lot of huffing and puffing. But the beauty and history made up for it.
I also have a very good friend, in her fifties, with two hip replacements, who went. She spent a long time training for the trip before she left. She also thought it was an extraordinary adventure (she chose to take transport as far as possible. My daughter was more intrepid and did more voluntary hiking.)
They both did their homework beforehand and so needed to ask fewer questions.
My friend compares it to her trip to the Great Wall of China. For the record, she has a new knee and is, this very minute, in New Zealand, kayaking and on her way to the Great Barrier Reef. She is prepared to be a mendicant with a begging bowl when she retires.