I had a blast running at Zion National Park. I ran from Hop Valley all the way down past the Grotto. I got a private shuttle to drop me off at the trailhead and then ran back to a shuttle stop where I took the bus back to my car. This run was net downhill. The last nine miles lost over 4,000 feet. While you might think running downhill is easy, it is not. Your body takes a pounding. I also sustained a minor injury during this run. If you don't like blood don't watch it. Always good to carry a first aid kit.