Slumgullion Pass — Lake City

This route is considered difficult, especially the climb from Lake City. It features the steepest continuously paved road in Colorado, with an average grade of 6.8% and sections reaching 9-15%. You'll gain approximately 2,737 feet (834 meters) over 7.6 miles to reach the summit at 11,530 feet (3,514 meters). Be prepared for a sustained ascent and the potential for altitude sickness.

The route is entirely on a paved, two-lane state highway (CO 149). While the road surface is generally in good condition, there is often no shoulder, and vehicles travel at highway speeds. The primary challenge comes from the steep and continuous uphill gradient, not rough terrain.

You'll cycle through thickly forested areas within the Gunnison National Forest, offering glimpses of spruce-fir forests and potential wildlife. As you ascend, you'll get excellent views of the canyon and Lake San Cristobal, Colorado's second-largest natural lake. Higher up, expansive vistas of the San Juan Mountains, including peaks like Uncompahgre, Matterhorn, and Wetterhorn, open up. The route also passes by the Slumgullion Pass summit itself.

Yes, the route is famous for the Slumgullion Earthflow, a National Natural Landmark. This enormous, slowly moving mudslide is responsible for the creation of Lake San Cristobal and is an active geological phenomenon studied by scientists worldwide. Interpretive signs along the way provide more information about this unique feature.

The best time to cycle this route is typically from late spring through early autumn. During autumn, the aspens transform, painting the mountainsides in brilliant gold and crimson, making it a particularly scenic time. Always check weather conditions, as the high elevation means temperatures can drop quickly, and early or late season rides may encounter snow or ice.

Specific parking information for cyclists starting directly at the base of the pass in Lake City isn't detailed, but Lake City itself offers various parking options. It's advisable to check local resources or visitor centers in Lake City for the most current and convenient parking locations suitable for starting a cycling tour.

Generally, there are no specific permits or fees required for cycling on Highway 149 over Slumgullion Pass, even though it traverses the Gunnison National Forest. However, if you plan to venture off the paved road onto designated trails within the National Forest, always check with the local Forest Service office for any specific regulations or permits that might apply to those trails.

While dogs are generally allowed in the Gunnison National Forest, cycling on a state highway like CO 149 with a dog can be challenging due to the lack of a shoulder and highway speeds. If you choose to bring a dog, ensure they are well-behaved, leashed, and that you have a safe way to transport them, especially given the route's difficulty and traffic conditions. This route is not typically recommended for cycling with dogs directly alongside you.

Given the high elevation and challenging nature, pack layers of clothing suitable for varying temperatures, including a windbreaker or rain jacket. Bring plenty of water and snacks, as services are limited. A repair kit, spare tube, and pump are essential. Don't forget sunscreen, sunglasses, and a helmet. Due to the potential for altitude sickness, consider bringing items like ibuprofen and being well-hydrated before you start.

Yes, while primarily a road cycling route, it does briefly intersect with some other paths. The route passes through sections of the Horse Park Trail, Sawmill Park Road, and the Lake To Lake Trail. These are generally short overlaps and are not primary features of the touring bicycle route itself.

Lake City, located at the base of the pass, is the primary hub for services. You'll find cafes, restaurants, and various accommodation options there. There are no services directly on the pass itself, so plan to stock up in Lake City before your ride.