We're thinking of visiting Rocky Mountain National Park for three or four days in the first week of October. Is it likely to be crowded?

I'm concerned because every hotel I've looked at is close to being sold out.

Color changing combined with elk rut seasons make for a busy time, but nothing like peak season. I'd make the reservations and enjoy.

Are there times when the Trail Ridge Road is open but it's not crowded?

No, not particularly. It is close to peak time in Sept and Oct. You have a couple of issues that are unpredictable. The fall Elk rut is a huge draw that clogs Trail Ridge Road if the rutting is close to the road. People just stop in the road with no regard for anyone around them. The rangers try but it is hard to keep the road open and traffic moving.

Depending on weather conditions the peak color season could be past since the peak tends to be in late September. That is also a big draw. And finally there is the risk of snow that can close Trail Ridge in a matter of a couple of hours.

The road is least crowded in early summer - June, July.

I fear my question was unclear. I'd like a time when RMNP is less crowded and the Trail Ridge Road is open and is not too crowded.

I was under the impression July was a crowded time for the Park?

It may well be that park and road are always crowded.

The area is extremely popular especially with out-of-state visitors so it always has a pretty good crowd.

Are you asking about a time of day? That is impossible to answer. Obviously, early in the morning would have less traffic. Now RMNP is open 24/7 and Trail Ridge Road opens Memorial Day weekend and is generally open till Nov but that is subject to how much snow is received. Once it states snowing then it is only a matter of time till the road is permanently closed for the winter.

And what do you anticipate when the road is "not too crowded."? What exactly are you asking?

The least busy time is towards the end of August when schools open and families have to be home for the start of school. Then after Labor Day it picks up again with all the retired folks, and many with RV, hit the roads because all the kids are in school.

If you can get accommodations, go ahead; it will be beautiful, and sitting in a lawn chair watching and listening to the elk is amazing. There's no set in stone rule about crowds (but I live 20 miles away find July to be very crowded...we mostly visit in autumn now).