Summer can be hot and crowded, with temperatures reaching up to 90 degrees Fahrenheit and large crowds of tourists. While the monument is still beautiful, the heat and crowds can make for a less enjoyable visit.
Fall can be a beautiful time to visit Mount Rushmore, with the changing colors of the leaves. However, the weather can be unpredictable, with the possibility of rain and snow.
Winter is the least popular time to visit Mount Rushmore, as temperatures can drop below freezing and the snow can make access difficult. However, if you're willing to brave the cold, you'll be rewarded with stunning winter views of the monument.