(MAMMOTH) The plowing of roads in the interior of Yellowstone National Park is making excellent progress, having only begun Monday. Park Spokesman Al Nash says crews have already opened 21 miles of road reaching Norris Junction and are now proceeding the 19 miles to Canyon. Nash says the good progress has been aided by crews not encountering ice build-up along the route. Once Canyon is reached, crews will begin work on the road between Norris and Madison Junction. Nash says it is still early in the project, but the good progress bodes well for being able to open the West Entrance on schedule April 18th.