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August 2, 2022

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Ironman Boulder 70.3 race in Boulder County on Saturday, August 6, 2022

Residents and travelers in the race area should plan for detours and increased travel times


Boulder County, Colo. - The Ironman Boulder 70.3 will return to Boulder County on Saturday, August 6, 2022. Please plan for detours and increased travel times in the vicinity of the race. All residents will have access to their homes, but road users may encounter delays and should follow recommended detours.

Due to detours, heavy traffic is expected on CO 119/Diagonal Hwy., though it will remain open to through traffic between Boulder to Longmont. All traffic will be shifted onto the Longmont-bound travel lanes to allow the bike course to use the Boulder-bound lanes.

View an interactive map, or course maps and more information on the Ironman Boulder 70.3 website: www.ironman.com/im703-boulder-course.

If you are traveling through the area during the event please pay close attention to the Boulder County Sheriff, Colorado State Patrol, and the volunteer traffic marshals who will be helping to ensure safety for riders and travelers alike.

When passing a bicyclist, motorists must allow at least three feet of space between their vehicle and a bicyclist. To pass a bicyclist safely, drivers may cross a double yellow center line when oncoming traffic is clear.

Travel restrictions and closures

The bike course will active between 6 a.m. and 2 p.m. and will use the following roads: CO 119/Diagonal Hwy., N. 63rd St., Monarch Rd., Niwot Rd., Neva Rd., US 36/N. Foothills Hwy, Nelson Rd., N. 65th St., St. Vrain Rd., Hygiene Rd. SH 66/Ute Hwy., N. 75th St./N. 73rd St., and 71st St.

  • N. 63rd St. will be closed to vehicular traffic from Monarch Rd. to SH 119/Diagonal Hwy. from 6 a.m. to 5:30 p.m.
  • N. 75th St will be closed to northbound vehicular traffic between Hygiene and Hwy 66 from 8 a.m. to 2 p.m. Residents will be allowed to enter their neighborhood, NO ACCESS TO CO 66 from Hygiene.
  • N. 71st St. will be closed to all traffic from Monarch Rd. to SH 119/Diagonal Hwy. from 6 a.m. to 2 p.m.
  • Niwot Rd. will be closed to all traffic from SH 119/Diagonal Hwy. to 71st St. from 6 a.m. to 2 p.m.
  • Monarch Rd. will be closed to all traffic from SH 119/Diagonal Hwy. to 71st Street from 6 a.m. to 2 p.m. and from 55th St. to 63rd St. from 6 a.m. to 5:30 p.m. Access to IBM will be allowed via 71st St. to Monarch Rd. - No access to IBM allowed via CO 119/Diagonal Hwy.
  • Hygiene Rd. will be closed from Hwy 36 to 75th St from 6 a.m. to 2 p.m. Residents will be allowed to access their homes.
  • Nelson Rd. will be closed from 65th St to 75th St from 6 a.m. to 2 p.m. Residents will be allowed to access their homes.
  • N. 51st/55th Streets will be closed to vehicular traffic from Jay Rd. to Monarch Rd. except to local residents between 7 a.m. to 2 p.m.

Please avoid crossing the course, if possible. If you need to get from one side to the other, please use US 36/N. Foothills Hwy., SH 66/Ute Hwy., Jay Rd., Airport Rd., and/or Hover Rd. to get around the course.

Avoid using Niwot Rd., Nelson Rd., or St. Vrain Rd. While these roads will remain open for resident access, you will experience longer delays than if you use the loop around the bike course. Law enforcement will be at all major intersections to help you turn or move through the racecourse, but you should expect delays if you are crossing the route.

For access to Bustamante Firewood and United Wood Products: Go to CO 119/Diagonal Hwy. and Airport Rd. and access via the Boulder-bound lanes. Drivers will not be permitted to travel southbound on CO 119/Diagonal Hwy. beyond Oxford Rd.

For access to IBM: Use Niwot Rd. or Oxford/Nimbus Rd. to 73rd/71st St., head south to Monarch Rd., and access via the East Loop Rd. Drivers will not be permitted to access IBM from CO 119/Diagonal Hwy.

Boulder Reservoir will be closed all day on Friday and Saturday, August 6 and 7, as well as the afternoon of Thursday, August 5.

Recreational cycling impacts

Recreational cyclists should avoid traveling in the same direction as the riders on the bike course and avoid traveling on and across the SH119/Diagonal Hwy. between 55th St. and Oxford Rd.

The IBM Connector Trail will be open to maintain cyclist access across the course on the CO 119/Diagonal Hwy.

Recreational cyclists may use N. 63rd St. from Niwot Road to the IBM Connector Trail, but they may not cross the racecourse at SH 119/Diagonal Hwy.

Spectator shuttles

All Ironman spectators must use the shuttle services to Boulder Reservoir from 7 a.m. to 2 p.m., no exceptions. Athletes and spectators arriving before 7 a.m. and after 2 p.m. must have a valid parking pass or utilize the shuttle services.

Shuttle Stops:

  • Boulder High School, 1604 Arapahoe Ave, Boulder
  • Holiday Inn Express, 4777 N. Broadway, Boulder

Questions or concerns

Questions or concerns may be emailed to Boulder70.3@ironman.com, or John Holste, Boulder County Special Events Coordinator, at jholste@bouldercounty.org.

Ironman Boulder bike course map 2022


Ironman Boulder run course map 2022