This trail is a real surprise. The Judith Mountains don't look like much from a distance, but the BLM has built a killer trail here with stiff climbs, great views, and sweet singletrack. To begin, follow the trail from the sign until it meets a road. DO NOT cross the road as you will soon meet a dead end. Instead, follow the road through a large gate. Be respectful of the easement through private property. Shortly after going through the gate, look for the singletrack on the left. Youve got a great climb for the first mile and a half. Then it's decision time--I suggest taking the spur to the Lewistown overlook. It's more climbing and the view may or may not be worth it to you, but the downhill return is screaming good fun. After you rejoin the main loop, there will be some more climbing before some wonderful, pine needle covered narrow and twisty. Some more climbing takes you to a ridge followed by another screaming descent and some very cool switchbacks back to your car. Beware, some of the log water bars have deep dips before them--time your wheelie well!
Go north from Lewistown on highway 191. 1/2mile north of town, turn right on Limekiln road (just after propane company and across the road from a grain elevator. Follow road about 7 miles until it dead ends at the Duvall Inn.
http://www.singletracks.com/item.php?c=1&i=2332