Replay Video We're sorry, there seems to be an issue playing this video. Please refresh the page or try again in a moment. If you continue to have issues, please contact us here. WATCH Loading Video... Mystery Tunnels 01:41 Brannon Smith and Scott Porter preview the team's trip to Pendleton, Oregon, to investigate a maze of tunnels that lead to a mysterious underworld. From: Darkness in the Underworld with Haunted Towns Similar Topics: Related Videos Poland's Nazi Tunnels 01:54 Mob Underground Tunnels 03:22 Yakutsk Permafrost Tunnel 01:25 Shanghai Tunnels Encounters 02:42 Quarry Mushroom Tunnels 02:15 Nopeming Sanatorium Tunnel 01:26 Recap: Sacramento Tunnels 03:44 Recap: Shanghai Tunnels 04:56 More Videos The Illuminati Tunnels 02:50 The iFly Wind Tunnel 02:18 Aaron's Vlog: Tunnel Search 00:38 Aaron's Vlog: Castle's Tunnels 01:03 Explore the Shanghai Tunnels 03:09 Lockdown in the Tunnels 02:36 Mystery Submarine 03:24 Mystery Room 03:01 Death Tunnel at Waverly Hills 01:23 Polar Flight Mystery 02:28 Mystery of Columbus 01:47 Easter Island Mystery 02:42 Andrew's Mystery Dinner 02:06 Mystery of Sleepy Sickness 04:15 A Toxic Medical Mystery 03:48 It Remains a Mystery 03:34 We Recommend First Family of Darkness Comes to Travel Channel with 'The Osbournes Want To Believe' Ghost Adventures: Cerro Gordo Ghost Town 13 Photos Small-Town Lore Takes Center Stage in 'Haunting in the Heartland'