And at that time of year the weather can change from 95 to 35 in an hour. Its not just the elevation, its them Rockies. You will be awed fellow rider. Get a couple of memory cards and spare batteries. As long as you're prepared you can scoff at those clouds.
Elevation sickness is serious. get the lungs ready and if you can get there early, get a hotel in Leadville and do some slow hikes.
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I think its disgusting and terrible how people treat Lance Armstrong, especially after winning 7 Tour de France Titles while on drugs!
I can't even find my bike when I'm on drugs. -Willie N.