I highly recommend the University of Colorado at Boulder. I'm slightly biased since I graduated there in May, but having spent my last four years there, I completely fell in love with the state and town. I've had to move away since I joined the army and have been gone for nearly 3 months and am already trying to figure out how I can get back.
CU is within about 1.5 hours of Keystone, Winter Park/Marjane, Loveland(which is a bit closer), Copper Mountain, Breckenridge, and Arapahoe Basin. It's 2 hours to Vail and 4 hours from Aspen. In my 4 years I managed to ski all of those mountains...there's great deals on season passes for students, $175 to Copper/Winter Park, and $350 for Keystone/ABasin/Breckenridge +10 days to Vail/Beaver Creek.
The school itself is right next to the foothills of the mountains and the campus is gorgeous. It has a very liberal student population, but you can walk any line you want to there(I'm a conservative military guy myself and loved it). It's only 40 minutes from downtown Denver. The student population is incredibly involved in outdoor sports like rock climbing, skiing/boarding, running, you name it. There's a reason why Outside magazine recently labeled Boulder as the #1 outside town to live in.
Going to school there was one of the best choices I've ever made.
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