Alum Cave is one of the most impressive points of interest in Great Smoky Mountains National Park. This gigantic rock feature requires a challenging 2.5 mile hike to reach it, but the reward is worth every step. The bluff of black slate is not only one of the largest in the region, but it has a rich background in salt mining and Civil War history that hikers can read about when they arrive. Anderson Design Group found inspiration from the yawning cavern mouth and surrounding forest. This early-1900s design captures the landmark's scale, with two visitors standing like specks in the cave's entrance. Order this vintage National Parks poster for your wall as a framed art print, canvas, or metal sign. To learn more about the Great Smoky Mountains, visit the Smokies Life.