This is a fun shuttle run from Brian Head Peak to Panguitch, Utah. There is nice singletrack, great scenery, and the route is almost all downhill. The last five miles go from singletrack to doubletrack to pavement.
At these elevations, be prepared for cold or stormy weather. I listed the trail as intermediate difficulty, but there are a few spots that will test a good intermediate rider. You can catch a shuttle at The Brian Head Giant Steps lodge and they will take you up to Brian Head Peak (11,300 feet elevation) and pick you up at Panguitch. As of the time of this posting, the shuttle was a bargain at $20. Of course, you can also self-shuttle.
Most people start by the small restroom just below Brian Head Peak. Look for a short steep singletrack climb that leaves the two track heading east. Don't get discouraged by this short climb. This is a downhill run. After about a quarter of a mile of climbing, you'll hit the top and ride through the tundra and scrubby trees that live above timberline. There are views in every direction. Be sure to notice Cedar Breaks National Monument in the distance to the south.
As you start the gradual descent into Bunker Creek look for views through the trees to the east. There are several great overlooks along the way. Follow the sign to the Right Fork of Bunker Creek (your left). It's the better bike trail of the two forks.
Now you'll drop in into the drainage and the fun begins. It's a very fun singletrack descent through the trees with a small stream crossing. Be on your toes, there are a few steep and rocky sections that will test an intermediate rider. Near the bottom, the trail changes to two track, but it's fast and fun.