What I can guess of the Highlands run at the most, around 3000 feet. Denver is known as the Mile High City because it's "official elevation" is 5280, Colorado Springs is around 6000. There are 50 peaks over 14k feet and quite a few more over 13k feet.
The Vail-Breckenridge ride I mentioned tops out at around 10500 feet with its lowest point at about 8000 feet. This page has a brief description of it. http://tinyurl.com/b5wxd
. A more extensive description can be seen at http://tinyurl.com/b37og