My boyfriend and I are seriously considering a big move out to Denver this upcoming summer. Obviously, one of my biggest considerations in a move will be where I can run. I know there are some serious trails out in Colorado (duh) but having never been out there, I'm curious to hear about the proximity of trails to Denver proper. I know there are plenty of running/bike paths in the city, but I'm more concerned with trails as I plan on training for a few ultras next year.  How far does one have to drive to get to some good trails?