The Lost Sea: Exploring America's largest underground lake in

Deep in the foothills of the Smoky Mountains, about 50 miles south of Knoxville, Tennessee, sits an wonder 140 feet below ground: the largest underground lake in America

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The Lost Sea, Sweetwater, Tennessee

The Lost Sea; America's Largest Underground Lake

The Lost Sea, Sweetwater, Tennessee

History - The Lost Sea

Discover America's Largest Underground Lake, The Lost Sea, in the Foothills of the Great Smoky Mountains - Smoky Mountain Events

The Lost Sea Adventure - All You Need to Know BEFORE You Go (with Photos)