Rising to an elevation of 9,624 feet, the Sonora Pass–Mono Road lies in the northeastern corner of Tuolumne County. Many visitors believe the road is one of the most beautiful mountain passes and also the most impassable in all of Tuolumne County. The pass lies at the converging point of the counties of Mono, Alpine and Tuolumne. As a wagon road, the pass was used to transport mining supplies beginning in 1864, and as the weekly passenger stage from Sonora to Bodie.
The jagged crest of the Sierra is the eastern edge of Tuolumne County and the boundary line for Yosemite National Park. The western slope is a sharp downhill featuring a series of granite domes, lakes and canyons.
Some historians believe that Jedediah Strong Smith was the first white man to cross the Sierra Nevada by using the old Sonora Pass Trail on his way to Salt Lake City, Utah in 1827. He is referred to as the “pathfinder of the Sierra.”
During the 1850s, visitors paid a toll at a crossing gate before they were allowed to enter the pass. Fine hotels and a stable was also located at the toll gate.
The Bidwell-Bartleson party, the first overland emigrants, reached one of the Sierra's highest ridges in October 1841 after several months of hardship. Their route over the mountains consisted of a series of gorges and steep canyons and progress along the ridge continued to be slow. Ten more years passed before thousands of miners, pack animals and wagons arrived to flatten and enlarge the faint trail to a well defined wagon road.
The Sonora Pass-Mono Road is now State Highway 108 and follows closely to the trail of the old Sonora Pass. The historical marker is located at State Highway 108 (P.M. 14.5) at Sugar Pine Cutoff in Sugar Pine. The road is also part of the Mark Twain and Bret Harte Trail.
A treasure of natural wonders and lively gold rush history, Tuolumne County offers visitors vivid scenery. A portion of Yosemite National Park lies within the county, along with giant redwood groves and impressive geological features. Both Bret Harte and Mark Twain wrote stories set in this area during the Gold Rush.