Watch Expedition Week online: Episode 4 Deep Secrets: The Ballard Gallipoli Expeditions

National Geographic Explorer-in-Residence Dr. Bob Ballard dives to the ocean depths searching for British and French warships that sank during the Battle at Gallipoli — one of the bloodiest and most controversial campaigns of World War I. We'll scour the warship graveyard using Nautilus, an advanced mobile research vessel with state-of-the-art electronics, computers, navigational and communications systems. It's the most comprehensive underwater exploration of shipwrecks from the Battle at Gallipoli ever taken. Now, stunning HD images from the sea floor could offer tantalizing new details about the Allied army's catastrophic loss and the tragic carnage left in the battle's wake. Read more: http://channel.nationalgeographic.com/series/expedition-week/all/Overview#tab-shows#ixzz16Ytg2x2Y

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