This is possibly the funnest/most challenging technical ride around. Start by riding up Pet-a-Kes. At the top, look to the east for the marker to the Holy Cross Trail. You should see the "Widowmaker" climb above you--fortunately you're not going there. Then, prepare yourself for the best ride you may ever see (if you're an advanced technical rider). The ride starts with some fun, flowy desert singletrack with a few small obstacles. Then, you get into the rocks, and over them, around them beside, them, and even under them. Some of the ride may feel like a trials course--few can complete it without walking. But the trail was well-designed, with great flow, and if you learn the course, it can become a real ruch to complete any of the challenging technical sections. Be careful when you hit the marked intersection with Gunny trail--go left. Pass by the entrance and exit to Miramonte, ride the top of the ridge, and finish with the switchbacks down to the parking area.
See the Pet-a-Kes trail for directions to the trailhead.
http://www.singletracks.com/item.php?c=1&i=2474