Do you want to explore America’s largest underground lake at The Lost Sea Adventure in Sweetwater, Tennessee? This is an experience you won’t want to miss!
The Lost Sea Adventure is a unique attraction that’s just about an hour northeast of Chattanooga. This incredible underground lake is hidden inside a historic cavern and is open for glass-bottom boat tours.
We did this as a day trip on our weekend trip to Chattanooga, and it’s such a cool attraction that I think everyone should know about!
If you want to take a glass-bottom boat on a crystal clear lake, and learn all about cave flowers and other geological marvels, then put the largest underwater lake in America on your bucket list! Here’s everything you need to know about visiting the Lost Sea Adventure.
About The Lost Sea Adventure
The Lost Sea Adventure takes you deep into the Craighead Caverns to The Lost Sea, America’s largest underground lake and the world’s second largest non-subglacial underground lake.
Your visit to The Lost Sea starts with a tour of the historic Craighead Caverns and culminates with an incredible glass-bottom boat ride on the underground lake.
Touring Craighead Caverns
The historic Craighead Caverns is full of rare formations as well as the largest underground lake in America.
The tour begins with the descent down a bright yellow tunnel and into the immense surrounding rooms of the caverns.
The caverns are large and open. Even though you won’t find such large-scale spectacular rock formations like you would at Ruby Falls or the Cathedral Caverns, Craighead Caverns still has rare rock formations at every turn.
The caverns are particularly known for their cave flowers (anthodites). These clusters of long, needle-like crystals form from the cave’s ceiling and drip down into flower-like formations. They’re incredible to see, and they’re only found in a few caves around the world.
There is also a formation called the “Bear Paw” that visitors can rub for good luck; as a bear lover, you know I rubbed it extra good!
The caves at Craighead Caverns have a long history of usefulness.
They’ve entertained a wide array of tenants: they were formerly used by the Cherokees as a meeting place; later, Confederate soldiers mined them for saltpeter to make gunpowder; in 1939 explorers found remains of a Pleistocene jaguar; the cave housed a mushroom farm from 1939 to 1940; and in 1947 a wooden floor was installed for the Cavern Tavern nightclub — the nightclub didn’t last long since it’s harder to get drunk underground in low altitude, but the booze will hit you on your way up the steep cave steps and you’ll come tumbling back down.
Glass-Bottom Boat Ride on the Lost Sea
The underground lake is the highlight of the tour.
There had been rumors of a large lake somewhere in the cave system for years, but this Lost Sea wasn’t discovered until 1905.
A young boy named Ben Sands, who often played in the caves, discovered the lake in this large room half covered with water. When he went home to tell his parents, they were skeptical. And he was finally able to bring his father back to the caves, the water level had risen and obscured the entrance! The lake was left undiscovered again for years.
The full extent of the Lost Sea is still unknown, but divers have managed to map out more than 13 acres of water so far. But they still have yet to find the end of the lake.
The Lost Sea Adventure management has introduced rainbow trout to the lake in hopes of finding where the lake flows out to, but the fish are content to stay inside the caves where they are well fed and undisturbed.
The tour takes you on a partially glass-bottom boat out into the 4.5 acres lake. During your tour, your learn about the system of underwater lakes and the many attempts to find the end of the Lost Sea.
And because I know you’re wondering, no you cannot swim in The Lost Sea. Sorry!
Wild Cave Tour
The Wild Cave Tour is a special tour that is for groups (like Scouts, schools, camps, churches, and more). You’ll get a regular cavern tour as well as a look into the undeveloped cave rooms on your overnight adventure.
This tour is a bit more like spelunking, and you’ll get to crawl through cracks and crevices.
The tour requires a minimum of 12 people and you’ll have to book at least two weeks in advance.
Old Sweetwater Village
Before or after your cave tour, you can enjoy a step back in time at Old Sweetwater Village.
Enjoy shaded walkways to authentic log cabins, pan for gems at Red Ruby’s Gem Mine, see a demonstration at the Glass Blower and Blacksmith Shop, and grab something to eat from the Sweet Shop and Cavern Kitchen Restaurant.
The Lost Sea Nature Trail
Take a quick walk along The Lost Sea Nature Trial. This 0.33 mile trail takes you through a hardwood forest made of a diverse community of plants and animals.
More Things to Do at The Lost Sea Adventure
Attend Special Events and Programs
In honor of National Caves & Karst Day, the caverns hosts a day of Tennessee-style music with several local bands playing throughout the day.
They also host Wild Cave Tours for organizations like schools, camps, churches, and scouts. And every Monday from August through May, you can bring your home school students for a special educational rate.
Find the Perfect Souvenir at the General Store
Shop around the General Store at the Old Sweetwater Village for a unique souvenir to take home from your adventure.
There is also a gift shop located at the entrance to where you can find more gifts and souvenirs.
Dine at the Cavern Kitchen Restaurant
The Cavern Kitchen Restaurant is located in the Old Sweetwater Village. This café offers sandwiches and a real pit barbeque.
The village also offers plenty of nearby picnic spots where you can enjoy your lunch.
Tips for Visiting The Lost Sea Adventure
The Lost Sea is situated 140 feet underground, so walking to and from the lake is a bit of a hike. The tour of the caverns includes a 0.75 mile walk, round trip. The temperature in the caves is always around 58 degrees, so be sure to bring a light jacket and some walking shoes that you don’t mind getting dirty.
Tours last about 1 hour and 15 minutes. Before and after the tour, you’ll be able to visit the small shops in the Old Sweetwater Village, take a walk on the surrounding Nature Trail, and browse the gift shop.
The Lost Sea Adventure is located in the Eastern Time Zone.
Location: 140 Lost Sea Rd, Sweetwater, TN 37874
Admission: Tickets to the Lost Sea Adventure costs $26.95 for adults, $15.95 for children ages 4-12, and free for children under 3.
Hours: The Lost Sea Adventure is open every day except Thanksgiving and Christmas. The attraction is open January and February from 9 a.m. to 5 p.m.; March and April from 9 a.m. to 6 p.m.; May and June from 9 a.m. to 7 p.m.; July from 9 a.m. to 8 p.m.; August from 9 a.m. to 7 p.m.; September and October from 9 a.m. to 6 p.m.; and November and December from 9 a.m. to 5 p.m.
Accessibility: The Lost Sea Adventure is not very accessible for wheelchairs. The pathways are wide enough for strollers and wheelchairs, but they are very steep in places and wheelchairs are not advised.
Parking: There is free parking where you can easily access the Old Sweetwater Village and The Lost Sea Adventure.
The Lost Sea Adventure FAQ
Can you swim in The Lost Sea?
Unfortunately, you cannot swim in The Lost Sea. But you do get to go out onto the lake in a glass-bottom boat.
How much does it cost to go into The Lost Sea?
Tickets to the Lost Sea Adventure costs $26.95 for adults, $15.95 for children ages 4-12, and free for children under 3.
How long is The Lost Sea tour?
The Lost Sea Adventure tour lasts about 1 hour and 15 minutes.
What should I wear to The Lost Sea?
Bring comfortable walking shoes for a 0.75 mile walk and a jacket as the caves are around 58 degrees. Make sure to wear shoes and clothing that you don’t mind getting a little dirty as the caves can be muddy.
How deep is The Lost Sea?
The deepest part of The Lost Sea is about 70 feet deep.
More Things to Do in Chattanooga
Explore all that Chattanooga, Tennessee has to offer! These fun itineraries will help you plan your perfect Chattanooga vacation.
- 3 Things to Do and See in Chattanooga, Tennessee
- How to Have a Girls’ Weekend in Chattanooga, Tennessee
- 5 Restaurants to Try in Chattanooga, Tennessee
- A Wedding at the Tennessee Aquarium
Ready to visit Chattanooga, Tennessee? Plan your trip with these tips.
- Book Your Flight: Find the cheapest flights using Skyscanner, my favorite flight search engine.
- Find Accommodation: You can find top hotels in Chattanooga using Hotels.com.
- Start Packing: Make sure you’ve packed everything you need with my packing list resources.
Have you visited The Lost Sea Adventure? Will you be checking America’s largest underground lake off your bucket list? Let me know in the comments!