“The outer, southern loop at Katie Jackson Park.
— Jason Rodda
This trail is maintained by the Dallas Off Road Bicycle Association. They don't mind runners, but keep an eye out for (and stay out of the way of) cyclists once you're on the trail.
A few zig-zags and a couple sharp turns make an interesting run through the forest even more so. Since this is a bike trail, keep an eye out for sharp and sudden hills and drops. Run the trail clockwise in order to keep an eye out for oncoming cyclists going the opposite direction. Signs at the trailhead make it clear which way is correct, based on whether you're biking or on foot.