The Oregon Trail is a 3,200 km historic east-west wagon route that connected the Missouri River to valleys in Oregon and locations in between. It flourished from the 1840s until the coming of the railroad at the end of the 1860s. The trip on foot took four to six months. It was the oldest of the northern commercial and emigrant trails and was originally discovered and used by fur trappers and traders in the fur trade from about 1811 to 1840. (source)
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