Last updated: June 13, 2026
Place
Big Mountain Pass
NPS Photo
Quick Facts
Location:
Approximately 19 highway miles northeast of central Salt Lake City. Take I-80 Exit 134 (eastbound or westbound) to enter US-65 and drive 8.2 miles to Big Mountain Summit; or from Henefer, UT, drive 19 mi on US-65/Emigration Canyon Road to the summit.
Significance:
Big Mountain Summit provided the first glimpse of Great Salt Lake Valley for westbound travelers on the combined California, Mormon Pioneer, and Pony Express trail corridor. The Donner-Reed Party blazed the first wagon trail up the east flank of the mountain and down the west flank in 1846.
Designation:
Historic site on the Mormon Pioneer, Pony Express, and California NHTs.
MANAGED BY:
Amenities
10 listed
Benches/Seating, Bicycle - Rack, Cellular Signal, Historical/Interpretive Information/Exhibits, Information Kiosk/Bulletin Board, Parking - Auto, Parking - Bus/RV, Scenic View/Photo Spot, Toilet - Vault/Composting, Trailhead
The Donner-Reed Party spent several days grubbing a wagon track from Little Emigration Canyon (at present Mormon Flat Campground) up the east flank of Big Mountain in August 1846.
The 4-mile climb starts at about 6,100 feet elevation and tops the summit at 7,420 feet, a gain of more than 1,300 feet. A year later, Brigham Young’s vanguard company of Latter-day Saints followed and improved that track over Big Mountain Summit, where they caught their first glimpse of Salt Lake Valley, their destination.
Thomas Bullock wrote in his journal on July 22, 1847, “I could not help shouting ‘hurra, hurra, hurra, there’s my home at last.’” Tens of thousands more Latter-day Saints and California-bound gold seekers, along with the Overland Stage and Pony Express, followed this trail to Big Mountain Summit in 1847-1869. Once at the top, they faced a hair-raising descent down the mountain’s west flank, which some claimed was “nearly perpendicular.”
They locked the wheels of their wagons with chains to keep them from turning and skidded straight down the mountainside. Some lowered their vehicles with ropes and some dragged trees behind to slow their wagon’s descent. One of the Donner-Reed wagons broke an axle on this stretch, and some later wagons did roll over and crash, despite the precautions.
Emigrant Mary Jane Tanner, following the vanguard in 1847, recalled, “As we gazed down the yawning chasm that lay before us the narrow road with rocks and bushes on either side, and leading we could not see where, was a sight to make the strongest heart falter.”
Mark Twain, traveling in 1861, wrote that his party arrived at the pass at 4 p.m. “when all the world was glorified with the setting sun, and the most stupendous panorama of mountain peaks yet encountered burst upon our sight. We looked out upon this sublime spectacle from under the arch of a brilliant rainbow! Even the Overland stage-driver stopped his horses and gazed!”
Big Mountain Summit is on US-65/Emigration Canyon Road approximately 19 miles northwest of downtown Salt Lake City. Walk to the southwest edge of the parking area and look toward the Salt Lake Valley to see the grand view once shared by Twain and others on the California, Mormon Pioneer, and Pony Express trail. Now examine the ground beyond the parking area. The deep scars that dive straight down the mountain are wagon ruts, gouged into the earth by skidding, iron-sheathed wheels and deepened by years of erosion.
Today’s UT-65 twists and turns down the mountain, crossing and recrossing the old trail scar. Watch for those crossings, marked with signs, as you continue west along the highway. Hikers and cyclists can retrace the challenging, 4-mile segment up the mountain’s east flank, starting from Mormon Flat Campground on Jeremy Ranch Road. Look over the northeast edge of the parking area to see the hiking/historic trail mounting the final, steep section to the summit. A second segment of the recreation trail begins west of the restroom.
Site Information
Location (Approximately 19 highway miles northeast of central Salt Lake City. Take I-80 Exit 134 (eastbound or westbound) to enter US-65 and drive 8.2 miles to Big Mountain Summit; or from Henefer, UT, drive 19 mi on US-65/Emigration Canyon Road to the summit.)