I picked “safe” but the real answer is “for fun,” (with safe being implicit).
My biggest fear is falling, which is why I love jumping off rocks into water. I’m a real chicken-shit about it, though; I can’t go as high up as most guys. Anything over 20 feet and it’s all I can do to convince my body to step out over open air. It just won’t go unless I trick myself!
The highest I’ve jumped seemed to me to be about 25 feet and one second of free fall. I be willing to bet that the actual measurements are probably half that. It was at Natural Arch Park in Queensland, Australia, where the waterfall ate a cave below and then opened up a hole into it, so the first half of the jump is through a say 10 foot diameter hole and the second half is falling through the big cave. I think it took me an hour to figure out how to fool my legs into allowing me to fall.
Then I found out what “scared stiff” really means. On the first jump, my arms went up (“I surrender” pose) and on the second one I wanted to draw them down to my sides. Mid air I realized that I could hardly move: apparently all my muscles were firing full force, and ANY movement was very difficult! Without thinking about it, I had always assumed “scared stiff” was purely mental, merely being immobile. Wrong!
For me, the scariest sensation is the one I’m sure I’d feel driving a car off a cliff. That’s why the Millennium Force at Cedar Point is such a head trip, years ago. The previous year I’d scared myself silly on the Magnum, which had been CP’s highest/fastest ride, but then they added the new MF, which was a lot faster/taller/scarier, and just the thought of it gave me the willies. So, my friends and I went to that first, and as luck would have it, I got the coveted first row seat (yikes). This ride accelerates as it goes up (unlike older rides where they slowly crank you up and then gravity takes you down.) It reaches an 80 degree angle on the way down (10 degrees short of vertical.) When you’re actually on it, it looks like it goes past the vertical, due to perspective.
I had to go to my safe place. But I survived, and we went back again for the last ride of the day, where I even managed to let go of the handholds and raise my arms above my head. I was so proud.