From the USPS press release November 15, 2024:

Covering almost 2,200 miles of footpath along one of Earth’s most ancient mountain ranges, the century- old Appalachian National Scenic Trail is within easy reach of large metropolitan areas of the East Coast. The Appalachian Trail is maintained by a network of volunteer clubs, led by the nonprofit Appalachian Trail Conservancy. This pane of 15 stamps includes a photographic view from each of the 14 states along the Maine-to-Georgia trail with an additional stamp showing stretches of trail through dense forest. Antonio Alcalá, an art director for USPS, designed the stamps with images from various photographers.