Need a break from the big city? View 42-hour itineraries from 13 cities.More
More than 80 percent of the park's annual 3 million visitors come in summer and fall. For thinner high-season crowds, come in early June or September. But there is a good reason to put up with summer crowds: only from Memorial Day to mid-October will you get the chance to make the unforgettable drive over Trail Ridge Road (note that the road may still be closed during those months if the weather turns bad).
Spring is capricious—75°F one day and a blizzard the next (March sees the most snow). June can range from hot and sunny to cool and rainy. July typically ushers in high summer, which can last through September. Up on Trail Ridge Road, it can be 15°F–20°F cooler than at the park’s lower elevations. Wildlife viewing and fishing is best in any season but winter. In early fall, the trees blaze with brilliant foliage. Winter, when backcountry snow can be 4 feet deep, is the time for cross-country skiing, snowshoeing, and ice fishing.