Snow-roads in Yellowstone...

The National Park Service does not plow the interior Park roads during the winter season. During a normal winter, several feet of snow builds up and covers the road surface. Because of this snow, the only access to the interior of the park is by snowmobile or "snow-coach". All oversnow vehicles in Yellowstone are required by law to stay on the snow covered summer time roads. This leaves the other 2 million acres of Yellowstone accessible only to cross-country skiers.

It is interesting to see how deep the snow was all winter when the roads get plowed in the spring. We have four to five feet of snow on the ground at the Skier's Camp by the time the plowing starts.