Emigrant Trail in Wyoming

The path followed by the Oregon Trail, California Trail and Mormon Trail (collectively referred to as the Emigrant Trail) spans 400 miles (640 km) through the U.S. state of Wyoming. The trail entered from Nebraska on the eastern border of the state near the present day town of Torrington and exited on the western border near the towns of Cokeville and Afton. An estimated 350,000 to 400,000 settlers traveled on the trail through Wyoming between 1841 and 1868. All three trails follow the same path through most of the state. The Mormon Trail splits at Fort Bridger and enters Utah, while the Oregon and California Trails continue to Idaho.

In the eastern plains, the Emigrant Trail follows the North Platte River into Wyoming. The trail follows the river upstream to Fort Laramie, a prominent military and trading post in the region. Prior to 1850 the northern side of the river was thought to be impassable beyond Fort Laramie, so the wagon trains that were traveling on the northern side of the river through Nebraska had to undertake a dangerous crossing at the fort. After crossing, trains on the main trail to the south of the river had to cross the North Platte again 100 miles (160 km) upstream. In 1850 several wagon trains successfully blazed a path along the northern side of the river. This new route, which reduced the risk and expense of crossing the river twice, was preferred for all subsequent traffic on the northern side of the river. The northern route is sometimes called Child's Route after Andrew Child who describe it in a guide book published in 1852. Above Fort Laramie, Child's Route follows the North Platte River through the present day town of Douglas, and near the site of Fort Fetterman which was built in 1867. This is the point at which the Bozeman Trail turned north to the gold fields of Montana in the 1860s.

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