It's certainly true that travel schedules and seasonal weather patterns dictate that the heaviest traffic flows to national parks come during the summer months. But that doesn't mean there's nothing to do in the parks in winter. At Dinosaur National Monument, for instance, a park that showcases geology, paleontology, and rivers in summer, winter brings opportunities for snowshoeing, cross-country skiing, and even snowmobiling.
Beginning January 1, most of the Harpers Corner Road, which you can access two miles east of Dinosaur, Colorado, off of U.S., and which runs 31 miles north into the monument, will close to wheeled traffic. But the first five miles of the road, up to Plug Hat Butte, will stay open and plowed throughout the winter to provide you with access to the Plug Hat parking area, from which you can ski or snowmobile farther into the monument as long as you remain within the road corridor.
Park officials say cross-country skiing and snowmobile use are allowed on the closed portion of the road beyond Plug Hat Butte. Snowmobiles are not allowed off the road surface and may not go past the Echo Park Road turn-off 21 miles north of Highway 40.
Additionally, the Split Mountain campground on the Utah side of the monument will remain open for the entire winter. The campgrounds at Rainbow Park, Deerlodge, and Echo Park remain open, but snowfall may prevent access to those campgrounds as the winter season progresses. Campgrounds have vault toilets but no running water. No fees are charged at these campgrounds during the winter season.
While I have yet to visit the monument in winter, I have made several excursions during warming weather and have stayed at the Split Mountain campground, which has some of the darkest night skies, and so some of the most spectacular star shows.