Take the long way:
U.S. 285 over Kenosha Pass and then down into South Park. At Fairplay, turn right on Colorado 9, which you'll take over Hoosier Pass into Breckenridge.
Over Willow Creek Pass between Granby and Walden Colorado
Between Crested Butte and Gunnison
Between Como and Breckenridge
Colorado 83 in Franktown
Take U.S. 285 to County Road 162 south of Buena Vista, past Mount Princeton Hot Springs, to St. Elmo in the Collegiate Peaks vicinity.
Between Divide and Cripple Creek
Between Divide and Cripple Creek Colorado
Colorado 306 between Buena Vista and Taylor Park
Woodland Park to Sedalia on Colorado 67
Estes Park and Rocky Mountain National Park:
Trail Ridge Road (US 34)
Flat Tops Country:
Between Buford and New Castle
Gold Camp Road:
From The Broadmoor to Cripple Creek
Golden and Golden Gate Canyon State Park:
Take Colorado 46 all the way through the park to the Peak-to-Peak Highway (Colorado 72).
Colorado 65 east of Grand Junction and north of Delta
Between Georgetown (I-70) and Grant (US 285)
Take I-70 to Glenwood Springs, then drive south through Aspen on Colorado 82 to U.S. 24.
U.S. 285 southwest out of Denver to South Park
from Aspen, Maroon Creek (Forest Route 125) to Maroon Bells (no cars, you'll have to go by bus or by bike)
US 50 from Salida to Gunnison
Morrison and Evergreen:
Head west through Morrison and up Colorado 74 to Evergreen.
Peak to Peak Highway:
Colorado 119, 72, and 7 between Black Hawk and Estes Park
Take I-25 north to Fort Collins, turn north on Colorado 14 and then west out of town and into the mountains. Drive along the Cache la Poudre River all the way over Cameron Pass to Walden, then go south on Colorado 125 through the Routt and Arapaho national forests back down to U.S. 40 at Granby.
Rampart Range Road:
Between Sedalia and Woodland Park
Elk River country north and Buffalo Pass east
US 24 from Leadville to Vail
Trail Ridge Road:
(US 34) through Rocky Mountain National Park
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