Colorado

I lived in CO for almost 30 years. If you google something like "cycling colorado" you'll come up with lots of info. How you arrange your trip depends of course on whether you want to go with a tour operator (like above post) or whether you're thinking of carrying your gear on your bike or whether you're more inclined to rent a vehicle and sample various parts of the state with day rides. There are a lot of (for lack of a better word) desolate, very exposed to sun and wind roads in the state so trying to piece together a route that's always great can be a bit of a challenge. However, for day rides, here are some of my favorites: from Estes Park to Granby over Trail Ridge Road (can be busy with traffic though); Idaho Springs to top of Mt Evans (14,000') this is really a classic and probably shouldn't be the first ride after you arrive-better to get some altitude acclimatization. There's some nice cycling in Summit County (west side of tunnel) including a bike path that goes over Vail Pass to Vail- don't let bike path put you off- this is a nice ride! You can do a circular route that goes from Copper Mtn- Leadville-Minturn-Vail- Copper Mtn. I think that this may be called Golden Triangle Ride. We always called it the Minturn Loop. Heading west, Independence Pass goes over 12,000' and can be ridden from Twin Lakes (east side) or Aspen (west). A nice short ride from Aspen up to Maroon Lake is lovely. Going further west on I-70, near Grand Junction, is Colordo National Monument. It's definitely a "wow" ride and was used frequently in various stage races in CO. Down in the southwest of the state, there's a beautiful loop from Durango to Ouray to Telluride and over Lizard Head Pass to Delores and back to Durango. There used to be some locals (maybe still are) who did this in one day on longest day of the year in June but I recall doing it a couple of times on really lightly loaded road bikes in 3 days. No fun to have to do such long mileage that you can't enjoy the scenery! Fall is really a great time to see CO but remember that Fall in that part of the planet doesn't last as long as it does in the UK and expecting consistently nice weather would not be realistic. You might get some snow even! September is usually nice but good weather in October is generally considered a bonus. Good luck and have fun with the preparation!