The Centennial Valley: Henrys Lake, Idaho, to Monida, Montana Professional Review and Guide
"This 51-mile gravel road skirts the Centennial Mountains, offering views across marshland and a valley bounded by the Gravelly and Snowcrest ranges. In autumn the foothills display groves of golden quaking aspen, in brilliant contrast to deep green conifers. Wildlife is abundant. As you follow the signs and head west, enjoy the scenic mountains to the south. They are the 10,000-foot Centennial Mountains, with aspen grove hemlines that shimmer golden in autumn. Ripping through the high plains from east to west, the Centennials make Red Rock Lakes National Wildlife Refuge one of the prettiest wildlife viewing sites in the state. Part of the road passes right through some of the aspen groves, which cast sparkling shadows.
Look for a safe place to pull over and walk among the trees. Many of them are genetically identical, since aspens clone themselves by sending out tremendous root systems, called rhizomes, from which new trees grow. Special attractions: Red Rock Lakes National Wildlife Refuge; backpacking, camping, fishing, floating, hiking, mountain biking, and wildlife viewing. This eTrail is a complete description of a scenic drive with a route map and information on the best travel seasons, interesting sites, recreation opportunities, camping locations, and much more."