Pinterest Facebook Twitter Email Mount Rushmore's Secret 02:55 Is there a secret vault inside Mount Rushmore? Find out. From: Monumental Mysteries and A Mysteries at the Museum Special Similar Topics: History Travel's Best Related Videos The Race to the Heavens 03:13 Grand Central's Mural 03:06 Top 10 Attractions in Denver 03:44 Can a Penny Kill You? 01:44 Blood-Drenched Temples 01:34 Fireworks at Mt. Rushmore 01:52 Black Hills & Native Americans 02:09 Custer State Park 01:40 More Videos Mt. Rushmore Maintenance 02:40 Wind Cave National Park 02:50 The Black Hills and Deadwood 01:31 Mt. Rushmore National Memorial 02:23 Nashville: Top 10 Locals List 06:18 Crazy Horse Memorial 02:09 America's Stonehenge 01:57 Remembering Charles Dickens 02:13 Murder in the Mansion 03:30 A Starlet's Invention 02:47 Excavating Ice Age Fossils 02:59 Theremin's Amazing Invention 01:13 Black Market Spirits 03:06 The Bombing of the Thinker 02:44 First Nuclear Test in History 02:29 Meet Balto, Hero Sled Dog 03:17 We Recommend Monumental Mysteries Special 9 Photos Greatest Mysteries: Sturgis Pictures 10 Photos Monumental Mysteries: Escape From Slavery Pictures 9 Photos Mysteries at the Museum 11 Photos