Looking to do a 3 week trip next year to north America and we generally like camping in the national parks when go there, which we manage every few years.
It won't be for climbing mostly general holiday bimbling but we would like to do some hiking and I would like to do some landscape photgraphy but generally not the roadside done-to-death opportunities.
I see from the NPS site that it can be a bit of a lottery for any of the higher campgrounds to be open by then, or even at all if there is exceptional snowfall through the winter.
Is it worth going that time of year and still enough to do to get the most out of the visit if higher campgrounds/access roads are closed or are we better off heading for somewhere warmer, further south or lower elevations?
Other options might be splitting the time between Rocky Mountains National Park and Yellowstone as we did a 2-3 week Yellowstone/Tetons trip a few years back which was great but was in August/September but I think late May looks like it presents a similar weather lottery to RMNP and YNP. Generally prefer shoulder season to avoid the crowds.
Ta.