Yellowstone has something to offer every month of the year. Summer is our busiest season with more than half our annual visitation occurs during June, July, and August. Spring and fall offer less crowds, but also cooler weather and fewer services. A winter visit will fill your days with snowy landscapes, steaming geyser basins, and fewer people. However, access to the interior of the park (e.g. Old Faithful, Canyon) is restricted to oversnow travel and many facilities are closed, so it's important to plan a winter trip well in advance.