I've always found there is nothing like a brisk walk to atone for sins of indulgence. So obviously, this particular weekend, a brisk walk just isn't going to be enough. What you need to work off that turkey is the Billy Goat Trail, one of the hiking trails of the Potomac Valley on the Maryland side, which offers what might be euphemistically referred to as a "challenging half-day's activity" over rugged terrain and spectacular scenery.

The nifty but out-of-print little "Potomac Trail Book" by Robert Shosteck describes it thus: "The entire riverside trail from Carderock to Great Falls for a distance of over eight miles has been designated the Billygoat Trail by a group of hikers who, in the 1930s, laid out, cleared and blue-blazed this rugged and picturesque route to the falls." Although you could do the entire trail in one day, it's made up of three segments, equally accessible from the C&O towpath. My experience is on the portion closest to Great Falls Park, referred to as Section A, which is the most demanding. Parking can also be demanding: On a nice weekend day, if you don't arrive before noon, the parking lot at the park fills up and there's no street parking left near Old Angler's Inn at the other end. So get going early.

Starting from Great Falls Park C&O Canal Historical Museum, walk 0.7 mile down the towpath to Lock 16, where the trail begins on the right. It starts off mildly enough through the woods, although you have to pay close attention to rocks and tree roots and look for the blue blazes. When you leave the woods behind, you come out on the rocky tops of the cliffs, known as the palisades of the Potomac or Mather Gorge. The blue blazes are now appearing on rocks instead of tree trunks.

You spend a lot of time picking your way from boulder to boulder, doing as much crawling as walking, it seems. The primeval starkness of all that exposed rock and sheer rock walls is just what's needed to live down that third piece of apple pie with whipped cream.

This hike is not for everyone (including young children, and dogs on leashes). I've seen people decide to give up and return the way they came, weighing the certainty of difficult terrain they have just been over against the possibility of worse terrain ahead. And it does get worse! Every step of the way is a step up, a step down or a step over. But it's worth it if you're unencumbered. Don't try this with the unsuspecting and out of shape, or if it is wet, snowy or icy weather.

The trail takes you from the cliff tops down to the river's edge, and a long and steep climb returns you to the towpath to finish this approximately four-mile circuit with a soft, unobstructed stroll back to the park.

And when you are done, you can all feel very thankful.

--Donna Murphy, Herndon

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