Wyoming's Newest Scenic Byway! An 80 mile stretch of U.S. 89 in Lincoln County has gained official recognition as the Star Valley Scenic Byway. The south end of the byway is milepost 54.9 where U.S. 89 crosses the Idaho state line a few miles north of Geneva Junction, Idaho., It continues from there at first east, and then north as it climbs Salt Canyon to the 7610foot summit of Salt River Pass. From the summit, U.S. 89 continues generally north as it descends into Star Valley, continuing through the communities of Smoot, Afton, Grover, Thayne and Etna before reaching Alpine. There, the byway continues to the east as U.S. 26-89 into Snake River Canyon to its northernmost point at the Lincoln-Teton county line about nine miles south of Hoback Junction.