Green Mountain
Credit: Tim Fitzharris / Corbis

Ask most Boulderites where an out-of-towner should hike, and they'll likely send you to Mount Sanitas, just blocks from downtown. While this tough climb offers stellar views of the town, it's perpetually jammed with hikers, runners, and dogs. Avoid the mule train and head to Green Mountain instead for a much-less-crowded, but just-as-challenging, 5.4-mile slog with even grander vistas. Take Baseline Road to the Gregory Canyon Trailhead, where you'll find a few trails to choose from, but bear right and head upward through the canyon. The first stretch is lung-busting, with several steep, stair-stepping sections, but it becomes more ramp-like once you join with the Ranger Trail at 1.4 miles. After a relatively easy cruise, the Ranger Trail starts switchbacking up to the Green-Bear Trail confluence, where you'll follow signs to the 8,144-foot Green Mountain summit. The final push is no joke, but you're mere minutes from the prize. Once you reach the top, scramble up one of the giant boulders to sit, catch your breath, and take in the stunning, nearly 360-degree view of Rocky Mountain National Park and the snow-topped Indian Peaks melting into the foothills that box in Boulder. Even the vast plains splaying out to the east are breathtaking from this aerial perch. Take the Saddle Rock Trail down, which is shorter mileage-wise but steeper than the way up.

More Information: For trail descriptions and conditions, visit