@BikeSnob not as nice as this but there are dedicated bike trails like this that go on for miles. My brother lives in Littleton and he takes a trail that goes around downtown Denver through a nice city park and around a nearby dam and back home and it's like 60 or so miles. But when I've gone to visit we ride almost 50 miles with no stoplights, and most importantly no cars. But the trails are endless.
Some trails lead into the street tho, but there are dedicated bike lanes.