The Cairngorms National Park is a year-round destination, but summer is the busiest season, bringing crowds and booked-up campsites. It's a good idea to try to avoid school holidays and weekends if visiting in the summer. Spring can be a great time to enjoy water sports, hiking, and climbing, free from crowds. From late February through March, you can also enjoy skiing and other winter sports. This is also a good time to visit the Cairngorms Reindeer Centre.