Highlands Ranch is great, the trails are pretty much beginner/intermediate - but a good work out and easily reachable from home (1 mile in my case). I figure closeness to SOMETHING matters a lot and you're more likely to get a work out in.
Then you can head for tougher trails like Dinosaur ridge, Deer creek canyon, Picks 'n Sledge, Green Mountain or any of the more challenging trails - longer tougher rides are worth the drive wherever you are. For me it is that 2-3 times a week opportunity out of my garage for a 7-9 mile ride.... more
Denver and Boulder are some of the friendliest communities to Hiking, Running and Biking. I know Denver has a ton of trails you can run and bike on that are off the main road. You can get all over town a lot of times without seeing any cars.... more
I have always had the the Epic pass, and that is Breckenridge, Keystone, A-basin, Vail and Beaver Creek. I have had awesome luck with that one. Winterpark and Copper mountain are a lot of fun as well. If you are looking for Skiing near denver there is Echo Mountain and Eldora they are smaller resorts but still fun I hear.... more
Our entire city has trails running through it. My advice is find a home that you love, and then worry about the running trails. The suburbs are full of them, but at the same time, the mountains (and Red Rocks for that matter) are only a half an hour drive.... more