The Lander Cut-Off of the Oregon Trail was constructed in 1858 as the first federally funded road west of the Mississippi River. After leaving the original Oregon Trail near South Pass, it crossed this mountainous region and rejoined the original trail east of Fort Hall, Idaho. The new trail saved considerable distance but substituted arduous mountain travel for the relatively flat route that traversed the dry desert in the south Green River Basin. Wagon tracks and lonely graves mark the passage of the early pioneers.