Following a short distance on Interstate I-90 (about 4.8 miles south of Clinton), the route follows the Rock Creek Road, a forty-two mile narrow and winding road through heavily forested terrain, of which only the first eight miles are paved. The route then goes through the historic town Philipsburg in Flint Creek Valley along the Pintler Scenic Route. The route then goes over an isolated Indian pass (Skalkaho Pass) through the Sapphire Mountains between Philipsburg and Hamilton in the Bitterroot Valley (about twenty miles of this road is unpaved), and then follows the Bitterroot Bike Trail back to Missoula.