The Atwell Tunnel Tree is nearly 25 feet in diameter level at the high side ground, 21.5 feet diameter at chest height, and 274 feet tall. It has one of the largest natural tunnels to be found, with an incredible ground-level perimeter of 110 feet and a cavern at the mouth of the tree on the downhill side that's 23 feet wide. The tunnel goes 22 feet through the tree to exit through a smaller opening on the high side of the tree. Locals sometimes refer to it as the Garage Tree, as in Flint's words it could "fit three economy cars inside."