This region was judged by U.S. Army Lieutenant Henry Mayandier in 1860 to be totally unfit for either rail or wagon roads and traversable only with the greatest difficulty as he attempted to map a wagon route across the Big Horn Basin. Yet after gold was discovered in western Montana in 1862, the need for a direct eastern route to the booming goldfield communities became clear so that freight and emigrants could reach them. In the spring of 1864, Jim Bridger guided 62 wagons from Fort Caspar through the Bighorn Basin to Virginia City, avoiding the Bloody Bozeman trail that crossed tribal lands east of the Bighorn Mountains. About 2,500 people in 10 wagon trains used the route during 1864, and Bridger led a second wagon train over the 510-mile route in the fall. After 1864, the route known as the Bridger Trail saw only occasional use because of the lack of water and grass, but its ruts and the memory of the man for whom it was named remained lasting marks in frontier history.