Guanella Pass runs from I-70 at Georgetown to US 285 just west of Bailey. For the full version of the pass, check out this post. The pass was paved in 2012 (but not quite all the way to US 285), thus adding yet another classic climb to a state that already has an embarrassment of riches in long, steep climbs. Start in Georgetown or better yet start in Idaho Springs. If you start in Idaho Springs , it is 24 miles one way with 4,300 feet of climbing. All but 1,000 feet happen in the 10.5 miles from Georgetown. There are steep sections at the beginning and end that flirt with double digits and a few small breaks as you work your way past a series of artificial reservoirs used to generate electricity through a pump-back process. By the time you reach the top (11,670 feet), you’re above treeline and the views of Mt Evans and Bierstadt are extraordinary. The climb will certainly become one of the classic Colorado climbs, as hard or harder than Squaw Pass from Idaho Springs, Vail Pass (from the west), Lefthand Canyon, and Golden Gate Canyon. As I understand the Rocky Mountain Cycling Club’s formula for difficulty, Guanella Pass rates as the fifth or sixth hardest climb in the state, right up there with Trail Ridge from the east and Molas Pass from the south.
There’s good parking in Idaho Springs at the lot behind Beau Jo’s and also next to the EMS station on Chicago Creek Rd, with free Forest Service bathrooms at the NFS Ranger Station. Don’t actually park in the Forest Service lot–it is for short term information and bathrooms only. The ride up to Georgetown along the frontage road you probably know from shortcuts in the winter when I-70 is backed up. When there’s no traffic, the ride is a sweet one, next to Clear Creek and with little traffic. Leave Idaho Springs on Colorado Blvd. Cross immediately to the south side as you reach the western outskirts of Idaho Springs. Ride upstream. Near Dumont cross back to the north side. This will be obvious because you just need to follow the paved road. Ride through Downieville (there’s a Starbucks there and a convenience store) and cross under I-70. Ride 1/2 mile to a fork. Go left to cross Clear Creek one more time and follow what’s known as Alvaredo Rd and CR 306 all the way into Georgetown. The road is in good shape.
Ride into Georgetown on what is now Argentine St. At the Y with Loop Rd, bear left on Brownell St. Turn left on 6th St, right on Rose St and you’ll be climbing for real in a few short blocks. The climb begins steeply with switchbacks, levels out for a few short moments near the hydropower reservoirs, and gets steep again at the top. You can read a detailed description in Russell Harding’s Blog, The Road to Cat 1, if you like to know in advance how much you are going to suffer. I know I adapt badly to altitude so reading a detailed description does not help me much. Anytime above 9,000 feet hurts. But here’s the profile if you’re a visual learner.
At the top, there’s a large lot to the west with a Forest Service outhouse if you need it. The views are great and the descent is fast and smooth, a treat if you’ve ever suffered coming down from Mount Evans, which you can see from the top to the east.