I often feel lonely in crowds, but I never feel alone in Nature.
The Colorado National Monument is a suburban National Park. The small city of Grand Junction is right at the bottom of the canyons - my Mother even lives off of "Monument Drive".
It's a great 23 mile drive. Rimrock Drive itself, blasted out by pickaxe and dynamite during the depression, is one of the main draws of the Monument. So, its a car park, like Zion and Bryce Canyon (Arches and Yellowstone require some walking).
You drive the loop, get out at the turnouts, take some photos of your friends or relatives with the Nature in the background, buy a dinosaur book for the kids at the Visitors Center, and you are quickly back on the Interstate. Barely any dirt to kick off of your shoes.