I loved climbing trees as a kid. In my front yard, we had two large trees - one for me to climb and one for my sister to climb. We even eventually made a flying fox across them (mid-way height), however we only tried it a few times and it didn't feel too safe so we took it down.

Thankfully I have never fallen from a tree.

If I ever saw an awesome tree, had a bit of free time, I'd so climb it.

I think the reason why it was so fun as a kid, at least for me, was that it was like an adventure where you could explore not only what was further up that tree, but your physical limitations and eventually feel good about your accomplishment of the height you achieved.