I guess I'm a mad freak.  Denver has many beautiful bike rides inside the city, beyond the Platte River and Cherry Creek bike paths.  Washington Park into the Denver Country Club neighborhood, up 7th ave then to Severn into Lowry.  Or Cheesman Park, to City Park, head to Five points then swing around to the Ball Park, maybe Lo Hi on to confluence etc.  Many nice rides out there if you dare to explore.