The Appalachian Trail
The Appalachian Trail is a 2,175-mile (3,500 kilometers)path that spans a mountain range along the eastern side of the United States, from Maine to Georgia [source: NPS]. This landmark is part of the U.S. National Park Service, so you could easily say you visited the trail by driving to one of the numerous public access points in any of the 14 states that this footpath spans. But if you want to brag that you actually walked the entire length of the Appalachian Trail, you'll need to prepare for an adventure that will last months. Hoofing it 30 miles (48.23 meters) a day, it will take you two and half months; a more casual pace of 10 miles (16 kilometers) a day will take you more than six months. Depending on how soon you want to complete this feat will determine whether you need a moderate or high level of physical conditioning. You can also break the trail into chunks over a period of years instead of attempting a thru-hike.
Looking for a shorter, but still challenging tour of nature?