I was doing some research for a novel that's in progress, and wanted to double-check something: so I went online and looked around. I found a thread asking, "What's considered 'a day's ride' for folks on a horse with average load over average terrain (relatively flat, even)? Not necessarily flat-out, but at a pace that won't wear out the horse?"
There were the usual thoughtful, considered answers, like "Anywhere from 15 to 30 miles is a realistic number to work with", or "Everything I've read indicates a good days travel on horseback is around 30 miles, more or less". However, this answer made me do a spit-take.
My daughter (and wife and I) started horseback riding lessons in February. Based on how my ass feels afterward, I'd say 200 yards.