Great Smoky Mountains National Park is a United States National Park and UNESCO World Heritage Site that straddles the ridgeline of the Great Smoky Mountains, part of the Blue Ridge Mountains, which are a division of the larger Appalachian Mountain chain. The border between Tennessee and North Carolina runs northeast to southwest through the centerline of the park. It is the most visited national park in the United States with over 11.3 million recreational visitors in 2016.