The first documented immigrant traverse of Sonora Pass appears to have been in the late summer of 1852 by a wagon train known as the Clark-Skidmore Company. Subsequently, merchant interests in the communities of Sonora and Columbia promoted the route to California-bound immigrants, not always with happy results when immigrants discovered how difficult it was. There are some references indicating the earliest immigrant crossing was in 1841 by the Bartleson-Bidwell Party, but the U.S. Forest Service indicates they crossed north of Sonora Pass in the Carson-Iceberg area.