Vail, CO
While the royals may not pursue business here, it may be a great place for them to relax and breathe in some of America's freshest air. In Vail Valley they can mingle with the locals with no worries of a frenzy of photographers much like they had in NY. They should take a stroll through the Betty Ford Alpine Gardens and maybe try skiing down Vail Mountain. They would benefit from taking a few days off to visit a quiet scenic atmosphere, far away from the noise and clutter of Britain.
[Photo via]