Yellowstone National Park is truly a once in a lifetime experience-but of course, you can always go more than once! The  Park boundary is only about 20 miles away from the Big Sky, and the Western Entrance (West Yellowstone, MT) is only about an hour's drive from Big Sky ! With it's wildlife & even wilder geological features, is not to be missed, winter or summer.  Wintertime brings opportunities to snowmobile or take a snowcoach to the Park's features.  Summertime brings opportunities to hike, bike, fly-fish or  enjoy ranger-led tours in one of the most beautiful places on the planet. 
 

See Yellowstone
Wintertime Snowcoach & Snowmobiling Tours
Summertime Scenic Van Tours
1-800-221-1151

Yellowstone National Park
Official Website from the National Parks Service