One major complaint from Coloradans old and new is the amount of traffic that clogs the roads to the mountains. There’s nothing worse than getting ready for a ski day only to be stuck in what essentially becomes a parking lot for hours on I-70. But is I-70 really the busiest road in the Centennial State? Here’s a look at a few of the most iconic roads in Colorado and how many cars travel them every day. These numbers come from the Colorado Department of Transportation, and represent an average of drivers per day based on totals for 365 days a year.

RELATED: 20 Highest Roads in Colorado!

11. Red Mountain Pass

Red Mountain Pass Photo Credit Jerry McBride Durango Herald - OutThere Colorado
One of Colorado’s most dangerous paved roads. Photo Credit: Jerry McBride, Durango Herald.

— 1,800 Vehicles Per Day (Technically open year round, but it closes periodically due to snow, mudslides, and rockslides.)

— 10.3% Trucks

RELATED: Colorado’s Most Dangerous Drive!

10. Highway 24 at Wilkerson Pass

Wilkerson Pass Overlook. Photo Credit: SnoShuu - OutThere Colorado.
Mountains stretch for miles at the Wilkerson Pass Overlook. Photo Credit: SnoShuu.

— 2,200 Vehicles per day

— 9.5% Trucks

9. Monarch Pass

Mountain views from a summit near Monarch Pass Colorado.
Views from a summit near Monarch Pass.

— 2,400 Vehicles per day

— 13.3% Trucks

8. Mount Evans Scenic Byway

Mount Evans - OutThere Colorado
A cyclist makes the climb up Mount Evans Scenic Byway, the highest paved road in the country.

— 890 Vehicles per day (2,700 per day adjusted for open dates totaling roughly 4 months.)

— 1.2% Trucks

RELATED: 20 Highest Roads in Colorado!

7. Hoosier Pass

Hoosier Pass Mountain Road OutThere Colorado
Storm clouds gather above Hoosier Pass.

— 3,800 Vehicles Per Day

— 6.3% Trucks

6. Highway 285 Between Denver and Fairplay

Alma - Larry1732 - OutThere Colorado
Highway 285 from Denver eventually leads to Alma, Colorado. Photo Credit: Larry1732.


— 5,300 Vehicles per day

— 9.1% Trucks

5. Trail Ridge Road

Trail Ridge Road High Drive OutThere Colorado
Trail Ridge Road, Rocky Mountain National Park’s heavily traveled highway to the sky.

— 4,300 Vehicles Per Day (10,500 per day adjusted for open dates totaling roughly 5 months.)

— 1.3% Trucks

RELATED: More About Trail Ridge Road!

4. I-25 Between Colorado Springs and Pueblo

Colorado Springs Pike's Peak Garden of the Gods OutThere Colorado
Lots of drivers commute from Pueblo to the more populated Colorado Springs each day.

— 35,000 Vehicles per day

— 9.9% Trucks

RELATED: 20 Highest Roads in Colorado!

3. I-70 at Idaho Springs

Weekend Warriors - OutThere Colorado
Traffic swells near Idaho Springs, Colorado.

— 44,000 Vehicles per day

— 7.6% Trucks

2. I-25 at Castle Rock

Castle Rock - OutThere Colorado
Castle Rock is a common spot for traffic jams for commuters between Denver and Colorado Springs.

— 73,000 Vehicles per day

— 5.8% Trucks

1. U.S. 36 Between Denver and Boulder at Superior

Flatirons - OutThere Colorado
While Boulder is only 30 miles from Denver, heavy traffic can often stretch this quick drive to over an hour.

— 82,000 Vehicles per day

— 2.2% Trucks

RELATED: 20 Highest Roads in Colorado!

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