I am a nature lover but not a skier, or interested in snow activities. what is a good travelling/soghtseeing season in Colorado?

If you are in good health, a classic challenge is to climb a 14er.

You need to tell us more about when you would like to go and your interests. There are some limitations in different seasons.

July, Aug, Sept are our favorite months-if not skiing

September and October. Southwest Colorado is grand - Durango, Telluride; Mesa Verde National Park are at their best in the fall.

Fall, for sure. Gorgeous weather, colors, everything is...gorgeous!

Thanks everyone. Fall it is.

Do make it early fall, snow starts in the mountains by October. Trail Ridge road was closed in the first week of October one year when we were there.

If you are coming from a warm state, colo can be a nice relief (cool) in august/september.

OP is coming from Australia

If you're not in the mountains, August can also be brutally hot. September-October is often glorious.

"Brutally hot"? Temperatures can reach 100 degrees but it does't happen that often and almost never in the mou tains. Now Phoenix in August gets brutally hot.

Oh, my, Sylvia. Puhleeze. LOL

I stand by my statement in reply to "colo can be a nice relief (cool) in august/september"

Colorado (the plains, not the mountains; note the caveat "If you're not in the mountains") can indeed be brutally hot in August, particularly if you don't stay indoors in, or have, air conditioning. Comparing it to, for example, Arizona, is pointless. Stating that August can be "cool" is simply wrong, unless you make it clear that 5000 feet elevation is very different from a mountain town at 8000 feet.

I guess it is how you define "brutally." Can there but a hot day in August? Of course, but on the whole Colorado is pretty mild with low humidity which makes hot days very tolerable.

On this one, Sylvia, you wrong. August can be cool and often is. There has been summer when the temperature was never over a hundred. And comparing to Arizona or other local where the temperature frequently climbs pass a hundred is exactly the point.

After 45 years of living here in Colorado, I can categorically state that I am not wrong.

Vail has a tremendous music scene in the summer.

The music/dance festival in Aspen is also world class; and many ski areas offer ride up/bike down or chairlift rides (along with alpine slides).

Thanks everyone. Can you tell me more about those music festivals? Now they are right up my street, especially if in a lovely environment.

They are all over the state. This is this year's calendar.
http://www.heyreverb.com/blog/2013/0...nd-more/67828/

http://www.aspenmusicfestival.com
The main venue is semipermanent, semioutdoors; walkable from many parts of town. Outstanding talent of all kinds, reasonable tickets, and of course the area is incredibly scenic. In the summer, Independence Pass (don't forget to visit the Grottos), the Maroon Bells, Castle Creek to Conundrum; outdoor recreation choices are innumerable, and there's a wide range of lodging types and prices.