Attractions - Caves
The Lost Sea Adventure: A Boat Ride on America's Largest Underground Lake
Family Fun
Hidden Gems
Deep inside a mountain near Sweetwater, in the foothills south of Knoxville, lies The Lost Sea, listed by Guinness World Records as America's largest underground lake. It is part of Craighead Caverns, a historic cave system and Registered National Landmark, and it makes a memorable day trip for families who want something entirely different from the Parkway.
Every visit is a guided tour. The route is a three-quarter-mile round trip that takes about an hour and 15 minutes, winding through large rooms and past clusters of anthodites, the delicate, spiky crystal formations known as cave flowers that appear in only a few caves in the world. Guides share the cavern's long history, including traces left by Cherokee people, Confederate soldiers and a prehistoric jaguar from more than 20,000 years ago.
The tour ends 140 feet underground, where electric-powered boats carry guests out onto the lake. The visible portion measures about 800 feet long and 220 feet wide, and divers have mapped more than 13 acres of water without finding its end. The cave holds at 58 degrees all year, so a light layer is wise in summer. Above ground, the Lost Sea Village and a renovated entry building with a gift shop round out the stop.
Photo: The Lost Sea Adventure
The guided tour is a three-quarter-mile round trip that lasts about 1 hour and 15 minutes, including the boat ride on the underground lake.
The cave stays around 58 degrees all year, so a light jacket or sweater and comfortable walking shoes are a good idea, even in summer.
It is open every day except Thanksgiving and Christmas. Hours are 9 AM to 5 PM from November through February, 9 AM to 6 PM in March, April, September and October, and 9 AM to 7 PM from May through August.
No. The lake is stocked with rainbow trout, but fishing is not permitted.
The Lost Sea advises purchasing tickets in advance to reserve your day and time and avoid a wait.
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