Sacajawea, the Shoshone woman who guided the Lewis and Clark Expedition, led Captain William Clark and his party of ten men over an old buffalo road through this pass on July 15, 1806. They were eastward bound and planned to explore the Yellowstone River to its mouth where they would rejoin Captain Lewis and party who were returning via the Missouri River.
In the 1860s John M. Bozeman, an adventurous young Georgian, opened a trail from Fort Laramie, Wyoming, to Virginia City, Montana, across Indian country east of here. He brought his first party through in 1863 and the next year guided a large wagon train of emigrants and gold-seekers over this pass, racing with an outfit in charge of Jim Bridger. Bridger used a pass north of here. These pioneer speed demons made as much as fifteen to twenty miles a day on good days. The outfits reached Virginia City within a few hours of each other.
In December 1883, the Northern Pacific Railway completed a 3,610-foot tunnel under the pass. By World War II, the old tunnel was badly deteriorated and couldn’t handle the bigger railroad cars of the time. The railroad began boring a new and wider tunnel under the pass in February 1944, completing it during the summer of 1945. The new tunnel, which is still in use, is 3,015 feet in length.
Slide toward Today to fade the historical sheet and see the modern map underneath.