We actually took two excursions with Colorado Sightseer - The Red Rocks, Evergreen, and Echo Lake Tour as well as the Rocky Mountain National Park Tour and they were both fantastic. Christin and Will were our tour guides and both were great! It's amazing how much knowledge they both have of the ecosystems, wildlife, and history of Denver. The groups were small, the vans were comfortable and nice, and it was very laid back - we felt right at home. We thoroughly enjoyed ourselves and our tours.