I spent a few of my childhood summers at a Girl Scout camp called Camp El-O-Win. They had a variety of activities, including a brief foray into horseback riding. This should have been one of the more interesting parts of the camping experience, considering it was up against 'bracelet making' and 'not getting poison oak'. The only other thing to really look forward to was the one shower you got towards the end of the week.
blissfully unaware of the dangers looming ahead
It was my first time riding a horse (unless you count carnival pony rides or this adorable photograph), so the counselors picked one out for me that would be good for beginners. I ended up with 'Molly', a big brown clunky thing that I assumed would be docile. Gentle. Nice. You know, "good for beginners".
So, that was wrong. This horse was an asshole. I had no idea how to control a horse, but that probably wouldn't have mattered. It completely ignored me, started galloping at random intervals and, about 20 minutes into the trail, stopped altogether and sat down on the ground.
I immediately leapt off the horse. It proceeded to flip over onto its back and roll around in the dirt, kicking its legs in the air while I watched, horrified. One of the counselors ran over and grabbed me, praising me for "knowing" what is, I guess, the correct procedure for not getting crushed to death by a horse.
I still don't know what prompted me to jump off so quickly. It's not like they gave us a class on what to do when your horse decides, "Naw, sick of this walking shit. Imma roll around for awhile." I guess it was instinct; possibly the gut knowledge that this horse was a dick and would totally try to kill me if it got the chance.
I haven't gotten on a horse since.