Marsh-Billings-Rockefeller National Historical Park

Built around the historic home of early American conservationist George Perkins Marsh, Vermont's only national park examines the relationship between land stewardship and environmental conservation. The estate's 20 miles of trails and carriage roads are free for exploring on foot, horseback, cross-country skis or snowshoes. There's an admission fee to the mansion itself, where tours are offered every 30 minutes.