As others have said, regarding RMNP...
Although Trail Ridge Rd
usually opens around Memorial Day, as noted in a previous post, that can vary. And "open" versus "safe to travel" are two different things. Yes, the Park staff are vigilant in getting the road
plowed and open but for general traffic purposes, it can usually take 1-2 additional weeks of plowing and cooperative weather to become generally safe for through traffic travel. Since I'm local and go up there A LOT, I'm usually one of the first to try my hand at going all the way across to Grand Lake. And it's been white knuckle time on more than a few occasions, even in my Tahoe in 4x4 mode.
Fall River Rd, even if it were not damaged by flooding, usually doesn't open until late June/early July. It's status for the upcoming year is questionable.
Aspenglen CG may or may not be open that early. Moraine Park, though it's open all year, will still have limited site availability beyond the "B" loop -- remaining loops usually are still snowed in until late May/early June. Glacier Basin, at a higher elevation, can be the latest to open for the season, and usually not until June.
The commercial CG in the Estes Park area usually open some time between May 15-30, depending on the weather and snow melt in Estes Park. Memorial Day is the traditional kick off of the season up there, with most of the stores/shops open by then; not always the case in the weeks prior. Again, weather dependent.
Coming up that early could be a huge disappointment due to limits, and that would be a shame, since there's so much to see/do there...when the weather is better!
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