Noun. wilderness; a
scenic roadless area frequented for
recreation.
Where skiers and hikers go to get away from it all ("All" meaning showers, toilets, and fresh food) and to be woken up at three o'clock in the morning by a hungry bear. While it can be part of a national park or scenic area, and there may be signs of use (trails, signage, blazes), the backcountry is less visited as it is typically roadless--accessible only via foot, skis, pack animal, or helicopter.
Adjective. Describing activities (skiing, camping) in, or objects created for use in, non-developed wilderness areas.
E.g., the phrase "backcountry medicine" describes medical practice in wilderness areas, with its difficult conditions (professional medical attention and equipment is two hours or more away, due to terrain, communication, and/or distance).