Directions: From the west side of Pocatello, follow Bannock Highway (Main Street) south, to get out of town.
Note: Bannock Highway is a continuation of South Main Street in Pocatello. Main Street is a one-way (north bound traffic) street located in the old downtown section on the west side of the railroad track complex (which bisects Pocatello into a east and west side). To access South Main (Bannock Highway), you need to get on Arthur Street which is a one-way (south bound traffic) and follow it all the way out of town. South Arthur merges into the Bannock Highway. Turn right (south) on the Bannock Highway.
Follow the Bannock Highway 3.9 miles until you see a street sign that says Gibson Jack (there's a large Chevron station just prior to the street sign). Turn Right (west) and travel approx 2.0 miles to the end of the road where you can park. You're now at the boundary of the Caribou National Forest and in the main branch of Gibson Jack Creek.
Trail Information: From the parking area, take the trail that leads west directly up the main canyon and creek. You will parallel Gibson Jack Creek. The area sees moderate use due to it's proximity to Pocatello and the nearby suburban subdivisions. You'll see few people after the first mile however. The trail trends southwest and then south and climbs an easy to moderate grade 3.5 miles from the parking lot to the divide into the Mink Creek drainage. You run through sage grasslands, aspen and conifers. Several beaver ponds are located in the creek. A nice bonus is the Forest Service exclusion of cattle grazing in the drainage. Aside from some horse packing dung, this ensures smells along the trail are natural and part of a great experience. Dogs are allowed.
At the top of the drainage, you may run back the way you came, or make a large loop run by continuing through a gate in the fence and on into the headwaters of west fork Mink Creek. A couple hundred yards south of the gate, the trail combines into the west fork Mink Creek trail. Turn left here and look up ahead. There's a fairly tall hill slightly on your left. You need to turn left off of the Mink Creek trail (about 1/3 mile from the gate at the divide, 4.0 miles from the main trail head) and take the zig zag trail (arduous) that climbs this tall hill. (If you miss this trail, you'll continue down into Mink Creek and ultimately 5 or six miles from your car.) After making the top, follow the trail down into the South Fork Gibson Jack canyon. It's now level or downhill the rest of the way from here. This trail will eventually take you back to the main Gibson Jack trail head and your vehicle making your entire run one grand loop. The loop run is 8 miles and takes about 2 hours if you don't stop much. It's my favorite Pocatello run.
Miscellaneous Information: Bring you own water (however, Gibson Jack creek is perennial). Tank up w/water for several hours prior to the run. Gibson Jack was a Shoshone Indian Chief. So was Pocatello. Good views of Pocatello valley and Portneuf mountain range from the loop trail. I've seen a lot of blue grouse, deer, occasional moose. A friend of mine has seen bear scat. Add'l info from the Forest Service at (208) 236-7500.