My husband spent 10 years in Colorado Springs years before we were married, and we vacation there almost every year. It's a great place! A couple more suggestions, in addition to the other excellent ones already given:
Helen Hunt Falls (includes hiking):
http://www.cheyennecanon.org/helen_hunt.html
Mt. Cutler (hiking):
http://www.stevegarufi.com/mtcutler.htm
I think both would be fine for kids as far as hiking, too -- they're not too difficult.
Oh, and the Cheyenne Mt. Zoo:
http://www.cmzoo.org/
Neat place --- you can even feed special crackers (that you have to purchase, of course) to the giraffes -- it's a lot of fun!
Have a great time! We're not going this year, unfortunately ... but we might move out there once I finish my RN and have a few years under my belt. We'll see.
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