Bluebell Rd., Chautauqua
In addition to hosting the Chautauqua Organization's lectures, films, and musical performances, this little enclave of summer homes (many of which can still be rented) is home-base for some of the best hiking in Boulder. The classic trail here is the Royal Arch, a two-mile out-and-back that climbs several switchbacks to a section of the flatirons that forms a golden, natural arch and offers sweeping views of the plains, with the city of Boulder laid out below you. From this trailhead, you can also link up with the Mesa Trail, a 7-mile stretch that crawls along the base of the mountains and runs the entire length of the city from North to South. Sure, it's a Boulder pilgrimage to complete the entire thing (down-and-back) in one day, but you can also access it in small pieces.