If you thought it was easy to plow the roads in Yellowstone National Park, guess again.

Park officials say plowing park roads is a monumental challenge each year. Unpredictable spring snow storms or other events can slow plowing progress. Sometimes roads have to be plowed several times because of weather. Each spring, park road crews clear snow and ice from 198 miles of main road, 124 miles of secondary roads and 125 acres of parking lots inside the park as well as 31 miles of the Beartooth Highway outside the park's Northeast Entrance to prepare for the summer season.

Most park roads are CLOSED to auto travel between early November and late April. The road from the North Entrance at Gardiner, Montana, through the park to Cooke City, Montana, via Tower Junction is open all year to auto travel. This year Yellowstone is scheduled to open to wheeled vehicles on the following dates:

April 18: Mammoth to Old Faithful; Madison to West Entrance; Norris to Canyon.

May 2: Canyon to Lake; Lake to East Entrance (Lake is one mile south of Fishing Bridge).

May 9: Lake to South Entrance; West Thumb to Old Faithful (Craig Pass)

May 23: Tower Fall to Canyon (Dunraven Pass); Beartooth Highway.

All Dates are Subject to Change

(Video- Courtesy of Yellowstone National Park)