MAMMOTH HOT SPRINGS — At 8 a.m. Tuesday, December 15, Yellowstone National Park will open to the public for travel by snowcoach and snowmobile. Between December 15 and mid-March, visitors can travel the park’s interior roads on commercially guided snowmobiles and snowcoaches from the North, West, East, and South entrances, weather-permitting. Visitors who have proper permits can also take non-commercially guided snowmobile trips.  

Traditionally, the East Entrance Road to Lake Butte Overlook (Sylvan Pass) opened December 22 and closed March 1 as conditions allowed. In October 2020, Yellowstone sought comments from the public about adjusting the winter operating dates for that segment of road.

After evaluating public comments and completing compliance requirements, the park recently made the decision to routinely open the East Entrance on December 15 and close it March 15, weather dependent. This change aligns operating dates for the East Entrance with other park entrances. The park annually opens roads in mid-December to oversnow travel only. Winter travel ends in mid-March when plowing crews begin to clear a winter’s worth of snow. Roads will start to re-open to automobiles in mid-April.  

The one exception is the road from the park’s North Entrance at Gardiner, Montana, through Mammoth Hot Springs to Cooke City, Montana. This road is plowed and open to automobiles all year. 

Winter weather is extremely unpredictable and road closures or delays can occur with little or no warning. Come prepared. Carry personal emergency survival equipment and dress appropriately for outside activities in extremely cold weather.  

Additionally, the park asks each visitor to recreate responsibly to reduce the spread of COVID-19. If you are sick, do not visit the park. Self-quarantine to avoid exposing others.   

Visitor services will be limited this winter, and dates may be subject to change. Check for updates at Explore in Winter.