NPS Photo
The parks are open 24 hours a day, 365 days a year, weather permitting. Highest visitation is in July & August. It can be difficult to find a campsite at popular campgrounds on summer Saturdays. Because of the extreme elevation range in the parks, conditions vary greatly from area to area and day to day. See the links above for more information on the season that corresponds to the time when you will visit the parks.