In an Aug. 1, 2012 photo, Crystal Stroud, 26, of Mississippi, rests and re-supplies with her 3-year-old Dachsund, Polly, in Harpers Ferry, W.Va. Stroud is hiking the Appalachian Trail northward from Georgia to Maine this summer. Like the people who hike it, the Appalachian Trail is always moving. Technically, Tuesday marks the 75th anniversary of its completion. But the 2,180-mile path stretching across 14 states from Springer Mountain, Ga., to Katahdin, Maine, is never really finished. (AP Photo/Vicki Smith)