According to the Associated Press, this is the second year the program is being offered. Last year, some 14,000 people participated in hikes that varied from cross country skiing treks in Alaska to a sunrise hike in Hawaii. Some had a historical focus, and were led by re-enactors in 19th century garb. All of the hikes will be led by Park Rangers, and most focus on discussions of the local flora, fauna and important sights along the way. Don't worry if you're not fit yet: most of the hikes planned are easy ones and a number are appropriate for people in wheelchairs (as they'll utilize paved paths).
I can't think of a better way to usher in the New Year!