The nearest state park has a nice 32 mile loop - if the rain would ever stop, it's a really nice day-ride with plenty of variety. Lots of hills, creeks and deep streams to cross, etc. I used to pack up a lunch and ride that loop for the day by myself whenever I could.
My boyfriend and I both have TWHs, and they cover a lot of ground when they move. When we go over to a trail in Indiana with a 8-9 mile loop, we ride it in one direction then stop back at the trailer for lunch, then ride it again in the opposite direction.
On a rougher/rockier trail we tend to take our time, and may not cover as much ground but just enjoy the scenery.
"Parelli horsemanship is just like painting by the numbers. You need absolutely no skill. You just put this color here and this color there, and when you're done, you have ... a mess no one wants." mp