The Utah Northern was intended to go at least to Soda Springs, but financial problems put the kibosh to that. The railroad, promoted by John H. Young—the son of Brigham—went bankrupt by 1878.
But Idaho’s railroad history was far from over. That first line to Franklin was quickly taken over by Union Pacific. At the peak, there were 2,877 miles of track crisscrossing Idaho. That peak was in 1920. Today, about 1,630 miles of track are in regular use in the state. By trains, that is. You can still hike and bike some of those abandoned rail lines, notably the Trail of the Hiawatha, Trail of the Coeur d’Alenes, the Ashton-Tetonia Trail, and the Weiser River Trail.