Last year I decided to challenge myself and signed up for the Sierra Club One Day Hike. They offer two options: 50k or 100k. I chose the 50k. I ended up walking 50k (or 31.07 miles) from White's Ferry to Harper's Ferry in about 8 hours on April 30, 2016. Just under 300 people participated.
If this piques your interest, we have plenty of materials to help you get started and Walk Like an Egyptian? Maybe not. These materials will help you think about walking as a way to get fit.
A search for the subject fitness walking in Catalyst yields both online and print books. Learn how to train and get the best health benefits from your walking workouts.
Where to walk? The One Day Hike takes place on the C&O Canal Towpath between Georgetown and Harper's Ferry. The benefit of this is that it's flat. I do most of my weekend walking on the Torrey C. Brown Rail Trail. If you're interested in other rails to trails, we have an online book about the trails in the Mid Atlantic region.