You don't say where your from, but I suggest you approach RMNP from the west side - Granby and Grand lake. Thee are some beautiful full service parks all through there. I am hoping to attend the Colorado Rally that is held in Ganby and will want to camp in the park afterward. I remember the camp grounds as rustic, but clean.That was 20 tears ago. However I suggest calling the park on trailer length and height restrictions Some information can be found through the park reservation system.

We stayed in Grand Lake, CO in 2021 in our 44' fiver. Had full hook up, but no cable or over the air TV that I can recall. The moose and elk passing through the RV park helped to make up for this. Grand Lake is at the west entrance to the park. Harder to get to and thus less crowded.

We stayed in Jellystone Estes park with our 303 a couple of years ago. Easy access to the park, full hookups, etc.

You are also not stating what time of the year. We were there just before Memorial day and not being in the park meant roadways were cleared quickly when the snow fell.

There were also food options for when we chose not to cook. Sometimes it's nice to eat breakfast somewhere and not have to worry about the cleanup.

Also found a nice KOA in Cripple creek, Stay as far up away from the entrance as possible. Snow still on the ground in May, and at our site the parking level was ABOVE our neighbors (space 150 I think). Great little place out of the way, back side of Pikes peak. Warning gravel road for about 1 mile to access the entrance. I ended up using the 4wd to get the camper up the park road more easily (prob could have done it in 2wd). Great view out both ways.

As I recall the sites we saw in the park were pretty tight. We stayed in Estes park at a campground right next to the entrance to RMNP. Fairly level sites and full hookups and the people were very nice. We enjoyed Estes park area and of course RMNP was epic.

Great suggestions.

We enjoy camping in the national parks, but were really concerned about what we were reading on Recreation.gov and Campendium.com about the space for campsites in RMNP.