CDOT will close a portion of US 550 during the annual Iron Horse Bicycle Classic May 23

Travel Advisory

May 18, 2026 Southwestern Colorado - Seek alternate routes from 7:30 a.m. to 1:30 p.m if traveling between Silverton and Durango

Southwest Colorado — To accommodate the annual Iron Horse Bicycle Classic, the Colorado Department of Transportation will close US Highway 550 to vehicle travel for approximately six hours on Saturday, May 23, between Purgatory Ski Resort and Silverton. Motorists must seek alternate routes between 7:30 a.m. and 1:30 p.m., or travel through the closure points before 7:30 a.m.

Motorists traveling north to Silverton early Saturday morning are urged to allow ample travel time to make it past Purgatory before the closure begins, leaving Durango no later than 6:30 a.m. The closure point north of Purgatory Ski Resort is located 25 miles north of Durango and is an approximate 45 minute drive from Durango.

“With multiple bicycle events taking place over the busy holiday weekend, drivers are reminded to eliminate distractions and pay attention to their surroundings,” said Colorado State Patrol Sergeant Ben Steger. “We expect motorists to drive safely, however, it is equally important that cyclists also stay alert and follow the rules of the road.”

Traffic Impacts: Saturday, May 23

Starting at 7 a.m. - Motorists headed southbound between Hermosa and Durango will be detoured from US 550 onto County Road 203 at Hermosa Creek to Animas View Drive. Northbound traffic from Durango to Purgatory will proceed along US 550 following traffic control personnel, signage and cones set in place.

Starting at 7:15 a.m.- Motorists will also experience brief delays and traffic impacts Saturday morning in Durango, along North Main Avenue, as several waves of cyclists are set to depart from 33rd Street. The first group of 600 professional cyclists will depart at 7:15 a.m., followed by approximately 1600 cyclists at 8 a.m. and at 8:15 a.m. a smaller wave of 200 cyclists will join the race.

From 7:30 a.m. to 1:30 p.m.- US 550 will be fully closed in both directions between Purgatory Ski Resort and Silverton (Mile Points 49 to 71). The highway will remain open north of Silverton, to Ouray, as always.

Alternative Route

Drivers may consider an alternate route via CO 145 through Telluride. This westerly route will add approximately one hour of additional driving time, taking approximately three hours from Durango to Telluride and ending in Ridgway (approximately 150 miles).

  • US 160 Durango to Mancos
  • CO 184 Mancos to Dolores
  • CO 145 Dolores to Placerville
  • CO 62 Placerville to Ridgway

Continuing south on US 550 to Silverton will add an additional 60 minutes of drive time (approximately 40 miles).

“For the past several weeks, CDOT maintenance crews have been maintaining and sweeping the highway to clear the road of debris, such as gravel and rocks,” said CDOT Maintenance Superintendent Mike Watson. “Motorists do not need to plan for additional construction delays, there are currently no active work zones along the US 550 mountain corridor."

For more information about the Iron Horse Bicycle Classic, visit ironhorsebicycleclassic.com

Map of US 550 closure and suggested alternate routes via CO 145 on Saturday, May 23, from 7:30 a.m. to 1:30 p.m. during the 2026 Iron Horse Bicycle Classic.
Map of US 550 closure and suggested alternate routes via CO 145 on Saturday, May 23, from 7:30 a.m. to 1:30 p.m. during the 2026 Iron Horse Bicycle Classic.

Know Before You Go

Travelers are urged to “know before you go.” Gather information about weather forecasts and anticipated travel impacts and current road conditions prior to hitting the road. CDOT resources include:

Remember: Slow For The Cone Zone

The following tips are to help you stay safe while traveling through maintenance and construction work zones.

  • Do not speed in work zones. Obey the posted speed limits.
  • Stay Alert! Expect the unexpected.
  • Watch for workers. Drive with caution.
  • Don't change lanes unnecessarily.
  • Avoid using mobile devices such as phones while driving in work zones.
  • Turn on headlights so that workers and other drivers can see you.
  • Be especially alert at night while driving in work zones.
  • Expect delays, especially during peak travel times.
  • Allow ample space between you and the car in front of you.
  • Anticipate lane shifts and merge when directed to do so.
  • Be patient!

Download the COtrip App!

The new free COtrip Planner mobile app was designed to meet the growing trend of information on mobile and tablet devices for the traveling public. The COtrip Planner app provides statewide, real-time traffic information, and works on mobile devices that operate on the iOS and Android platforms. Visit the Google Play Store (Android devices) or the Apple Store (iOS devices) to download!