We are planning a 7 day trip to Colorado in July and can't decide between going to Ouray or RMNP. We like mountains, lakes, nature, hiking and also historic sites

-- Option 1 (RMNP & Estes)
Stay at Estes and visit RMNP. Lots of nice hikes. A visit to Boulder

-- Option 2 (Ouray)
Explore Ouray (this looks so nice)
Drive down Scenic 550 (mill doll hw)
1 Day Trip to Verde Mesa (big plus)
1 Day Trip to Durango

Well, let me confuse the issue even more. Do both in 7 days.

Day 1 - arrive/ fly into Denver and go to Estes Park
Nights 1 - 3 in RMNP
Day 4 - drive to Durango via Ouray
Night 4 - Durango
Day 5-6 - Mesa Verde and Durango area
Day 7 - return to Denver
(I'd return via Great Sands NP and back a big loop back to Denver)

7 days doing the Best of Colorado

I would advise the same as starrsville - do both. It's not that much driving, and you will really enjoy the spectacular scenery along the way.

But, if you are committed to only doing one or the other, I would definitely pick Ouray. However, I would split your time even that way - a couple of days in Ouray with trips to Black Canyon of the Gunnison, Telluride, Silverton and the Million Dollar Highway; and a couple of days based in Durango with day trips on the Durango/Silverton Narrow Gauge Railroad, or to Four Corners. Absolutely include Mesa Verde, but if you can, stay one night in the park at the Far View Lodge. It is an incredible experience.

I vote for Ouray. Take a jeep ride up to Yankee Boy - the wildflowers will be in bloom while you're there. Check out their small, but very interesting historical museum. And then soak in the hot springs pool.

Mesa Verde is fascinating. If you loop around, you can include Telluride.

If you did a search here you would see how many people enjoy visiting the Ouray area and all the things there are to do there.

You could spend a week there seeing everything:

Jeep ride--1 day
Durango/Silverton Railroad--1 day
Mesa Verda N.P.--1 day
Spending time driving the area and seeing Black Canyon and visiting the charming towns of Ouray, Silverton, Telluride, Lake City, Durango, etc.--at least 2 days.

I don't like to go back to places I've been-I like to see new things BUT we love going back to this area. After traveling all over the US Rockies for years, this is our favorite area, outside of Yellowstone/Grand Tetons and Glacier N.P.'s.

We have been going to CO. for over 18 summers..Its always hard to pick a spot!...after all these yrs.though for ease convience and EVERYTHING else you mentioned you would like to do, look at the LAKE DILLION area in Summit County. You can do day trip to RMNP..you can hike two easy 14,000 ft.peaks, Gray & Torrey. Hike Loveland Pass, Drive up MT Evans, another specatacular day trip..Historic Georgetown & the RR, Leadville, South Park..Lots of condo's to choose from and very affordable. Tons of 4wheel rodes up Montezuma Rd..MILES of paved bike trails, I could just go on & on..this is all about an hr. ride up I-70...for a weeks visit, don't spend it driving all over!. ENJOY being outside.Even a week here is never enough..I miss it always!