Between December and March, the Park Service closes all but one of the roads that criss-cross Yellowstone National Park. Once there is sufficient snowfall, usually by mid-December, the remainder of the park is open to over-snow travel only—this means snowmobiling. This means you can experience all that Yellowstone has to offer, from geysers and other geothermal features to the Grand Canyon of Yellowstone and its incredible waterfalls—which don’t typically freeze in the winter—all from the back of a snowmobile. It’s also a great way to see the park’s active winter wildlife, like its famous wolf packs and bison herds. The park offers commercially-guided snowmobile tours, as well as a non-commercially guided snowmobile program. Check with park headquarters for more details. Winter lodging is available in the park at Mammoth Hot Springs. Otherwise, the Yellowstone Gateway Inn, located in nearby Gardiner, Montana, is an excellent option.