Hardly. Leadville is 10,500. But I agree with the terrain thing. We have climbs in the sierra's that match, rival, and stomp most if not all the Alp's climbs. Onion Valley Road (imagine a giant crowd with a peloton knifing through on those switchbacks!), Mt Evans in Colorado would be a neat stage finish. And what is considered the hardest road climb maybe on earth is in New Hampshire on Mt.Washington. Start the event in California with a prologue and a few stages, hit the Sierras and creep east through the rockies and plains. do a penultimate stage on mt washington or brasstown bald and end with laps around Washington D.C. (just daydreaming i know.)
The highest town in America, Leadville, is 12,000 feet.