NCAR and Flagstaff via Chapman Drive, Boulder Canyon, and Bear Creek loop from Table Mesa — Gravel

This route is considered a hard gravel ride, demanding very good fitness. While Komoot rates it as 'moderate', be prepared for substantial elevation gain (over 730 meters) and challenging climbs like Chapman Drive, which has an average gradient of 7%. Some unpaved sections might even require pushing your bike, especially if the ground is wet.

The loop features a diverse mix of surfaces. You'll ride on paved roads, bike paths, and unpaved sections. Key unpaved areas include about 2 miles of packed gravel on the Boulder Creek Path and the 2.6-mile dirt/gravel fire road of Chapman Drive Trail. The Bear Creek Trail segment typically involves wide singletrack or dirt trails. Approximately 87% of the route is paved, with about 6.38 km of unpaved sections.

You'll experience diverse and stunning views. Near the National Center for Atmospheric Research (NCAR), you'll find wide-open spaces and excellent views of the iconic Flatirons. As you climb Chapman Drive Trail, you'll enjoy forest shade and scenic vistas. The Boulder Creek Path (Boulder Canyon) offers pleasant views alongside the creek, and Flagstaff Road Scenic Drive provides picturesque views of the surrounding landscape.

The route is enjoyable in various seasons, but spring and fall often offer the most pleasant temperatures. After spring rains, you might see abundant wildflowers. Be aware that winter conditions can make unpaved sections more challenging. Always check local weather and trail conditions before you go.

The route starts from Table Mesa, which is a common access point. You can find parking in the Table Mesa area of Boulder. Alternatively, public transport options are available to the NCAR area or Table Mesa, allowing you to start your ride from there.

This route is located within Boulder Open Space and Mountain Parks. Generally, there are no entrance fees for accessing these trails. However, it's always a good idea to check the official Boulder Open Space and Mountain Parks website for any specific regulations or permit requirements that might apply to certain activities or areas, especially if you plan to use specific facilities.

While many trails in Boulder Open Space and Mountain Parks are dog-friendly, specific regulations apply, including leash laws and voice and sight control requirements in certain areas. Since this route includes various trails and roads, it's best to check the specific rules for each segment, especially for Chapman Drive Trail and the Boulder Creek Path, on the Boulder Open Space and Mountain Parks website before bringing your dog.

Given the mixed terrain of paved roads, packed gravel, and dirt fire roads, a gravel bike is ideal for this route. A robust road bike with wider tires (at least 28-32mm) could also work, but a gravel bike will offer more comfort and capability on the unpaved sections. Ensure your bike is in good working order, and bring essentials like water, snacks, a repair kit, and appropriate layers for changing weather.

Yes, a significant feature of this route is Chapman Drive Trail, which is closed to motorized traffic. This provides a peaceful and safer climbing experience. The Boulder Creek Path (Boulder Canyon) also offers a car-free approach to the base of Chapman Drive.

As of April 2025, there was ongoing construction at the Chapman Drive Trailhead and a segment of the Boulder Canyon Trail. These works may lead to detours. It's advisable to check local Boulder Open Space and Mountain Parks alerts or signage before your ride to be aware of any safety precautions or temporary closures in these construction zones.

Yes, this loop seamlessly connects several key cycling areas and trails in Boulder. You'll ride sections of the Boulder Creek Path, Chapman Drive, Flagstaff Trail, and Bear Creek Path. Other official trails along the route include the B360, B180, Goose Creek Greenway, and Broadway Path, among others.