of Rock Springs. This segment of the route is known locally as "East Flaming Gorge Road." The route is then concurrent with Interstate 80 eastward for approximately , passing just north of Rock Springs. US 191 diverges northward at Exit 104, following the former route of US 187. Traveling through high desert country, the route passes through Eden, Farson, and Pinedale before meeting US 189 at Daniel Junction. Continuing north, the road traverses increasingly mountainous terrain, entering the Bridger-Teton National Forest and passing through the small community of Bondurant before descending through the narrow Hoback River Canyon to an intersection with US 26 and US 89 at Hoback Junction. The route then follows the Snake River valley northward to Jackson. US 191 is concurrent with US 189 between Daniel Junction and Jackson, and with US 26 and US 89 between Hoback Junction and Jackson. North of Jackson, US 191 soon enters Grand Teton National Park, running concurrently with US 26 and US 89. The highway meets US 287 at Moran Junction, inside the park; US 191, US 89, and US 287 are concurrent north of Moran, but the highways are not signed. Continuing through forested, mountainous country, the route passes through the John D. Rockefeller Jr. Memorial Parkway before ending at the South Entrance of Yellowstone National Park. While US 191 and other U.S. Routes are officially discontinuous through the park, some commercially produced maps show these highways running inside Yellowstone National Park itself along its unnumbered roads and across the Wyoming–Montana state line. Montana US 191 in Montana begins at the West Entrance to Yellowstone National Park, at the edge of the town of West Yellowstone. The highway heads north, running concurrently with US 287 for before veering slightly east and entering Yellowstone. US 191 continues northward through Yellowstone, traversing forested, mountainous terrain and briefly looping into the state of Wyoming, before leaving the park in the upper reaches of the Gallatin River canyon. The route travels northward through the narrow canyon, past the resort community of Big Sky, then entering the Gallatin Valley near the town of Gallatin Gateway, Montana. US 191 travels north and east through the valley to the city of Bozeman, which is the largest city along the entire US 191 route. From Bozeman, US 191 is concurrent with I-90 eastward to Big Timber, where it proceeds north. The road travels through hilly ranch country