Sorry for the late programming note, but just got word that the National Geographic Channel will explore the Appalachian National Scenic Trail tonight.

The Park Service’s National Trails System Map can serve you well, but be aware of its limitations.

This week’s quiz deals with wilderness in the national parks. Answers are at the end. If we catch you peeking, we’ll make you memorize the entire list of designated wildernesses.

Zigzagging 2,175 miles between Mount Katahdin in northern Maine and Springer Mountain in Georgia, the Appalachian National Scenic Trail gained life through an article Benton MacKaye wrote for the Journal of the American Institute of Architects in 1921. In it the forester ruminated on the need for Americans to spend more time at leisure, preferably in the outdoors.

A wheelchair accessible 900-foot section of the Appalachian Trail recently opened along the Ottauquechee River near Killington, Vermont. That makes the fourth section of the AT designed for accessibility. A fifth is under construction near West Point.