Big Cottonwood Canyon drew 15,300 vehicles on an average fall Saturday, nearly double the 8,900 it saw on Saturdays in May 2026. The figures come from Utah Department of Transportation (UDOT) traffic sensor data first reported by ABC4.

Little Cottonwood Canyon matched the surge. Saturday traffic there jumped from 6,900 vehicles in May 2026 to 15,000 during the same fall stretch. Both canyons sit at the end of Wasatch Boulevard, minutes from Sandy neighborhoods.

On weekdays, Big Cottonwood averaged 9,300 vehicles daily, up from 4,700 in May. Little Cottonwood averaged 5,300, up from 3,500. During peak hours in Big Cottonwood, more than 1,200 vehicles passed through the canyon mouth in a single hour.

The Alpine Loop's American Fork entrance recorded 12,000 vehicles on Saturdays and 5,700 on weekdays, also roughly double May figures.

When to go

UDOT's Cottonwood Canyons guide says fall foliage peaks in late September through early October. Higher-elevation areas like Guardsman Pass turn first, and color moves down the canyons over the following weeks. Colors can last through October but depend on weather, according to UDOT.

UDOT advises visiting on a weekday to avoid the worst traffic and parking conditions. The Utah County Sheriff's Office says the Alpine Loop (SR-92) is busiest between noon and 6 p.m.

Before you drive

The Sheriff's Office asks Alpine Loop visitors to park with all wheels off the pavement, slow down on the narrow road with no centerline, watch for wildlife and cyclists, and note that vehicles over 30 feet are not recommended on the tight switchbacks.

Dogs are banned in Big Cottonwood Canyon. That includes dogs inside a vehicle, under a Salt Lake City ordinance. Roadside parking along Guardsman Pass Road is prohibited, and vehicles parked on the shoulder may be ticketed and towed.

Trailheads including Cardiff Fork and White Pine require a U.S. Forest Service pass. A three-day pass costs $10, a seven-day pass runs $20, and an annual Uinta-Wasatch-Cache pass is $60. An America the Beautiful Pass costs $80.

Transit option

Park City Transit's 9 Purple Route runs Fridays, Saturdays and Sundays until Saturday, Oct. 31, connecting Old Town Transit Center to Bonanza Flat Trailhead and Bloods Lake Trailhead. The shuttle is free and allows bikes and dogs.

Looking ahead

UDOT completed a Big Cottonwood Canyon environmental assessment in May 2026 and approved a $264.5 million plan to ease winter congestion. The project includes a 1,750-stall parking structure near the canyon mouth, frequent bus service and a variable-priced toll. Devin Weder, UDOT's Cottonwood Canyons transit program manager, said in the May announcement that the improvements aim to "give people another reliable option to reach the canyon without sitting in hours of traffic." Transit service could begin as early as the 2028 winter season.

Upcoming

• Through Saturday, Oct. 31: Park City Transit 9 Purple Route to Bonanza Flat and Bloods Lake trailheads, free, Fridays through Sundays
• 2028 winter season (estimated): UDOT transit improvements in Big Cottonwood Canyon begin