Here is good news to all all-season outdoor enthusiasts: The area around Deep Creek Lake, MD is not only in summer a wonderful playground, but offers lots of outdoor activities in winter, too.
For example, the Herrington Manor State Park offers 10miles of groomed trails. If this is not enough, there also is a 5.5 mile trail to connect Herrington Manor with Swallow Falls State Park. Enjoy the beautiful scenery and the quiet in the woods, then go back to Herrington Manor and warm up in their warming hut where you can also can get something to eat and drink. Trail conditions can be checked out on their website.
Even if you don’t have x-country skiing equipment yet, you can still give it a try. Simply rent skis and boots at the park, other than that you can wear whatever you would wear for a run. Don’t wear to thick clothes, you will get warm pretty soon from the exercise.