Lake Pend Oreille is one of the most popular lakes in Idaho. This massive body of water is Idaho’s largest lake at 43 miles long and with 111 miles of shore. It is a popular place for boating, fishing, camping, swimming, picnicking, and so much more. But it also has a few unique secrets that make this lake stand above the rest. For example, did you know this lake is bottomless?

Well, technically, Lake Pend Oreille is not bottomless but it certainly feels that way. At 1,158 feet deep, it is not only the deepest lake in all of Idaho, but there are only four lakes deeper in the entire United States!

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This lake is not only deep but it’s quiet and calm, creating the perfect combination. In fact, this lake is home to the Navy’s NSWCCD Acoustic Research Detachment (ARD), which uses this ideal lake environment to research, test, and evaluate submarine technology such as submarine acoustic stealth technology.

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While your day at the lake likely won’t be to test advanced technology, there is still plenty to see and do. If you want to spend time on the water, hop on a ski boat, sailboat, kayak, and paddleboard. If you don’t have your own, you will find multiple rental companies around the lake.

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You can always just enjoy the water from the shore on one of the many beaches or picnic areas. This is a great way to spend a relaxing day outdoors.

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There are even state parks located around the lake, like the stunning Farragut State Park.

Tree To Tree Idaho/Facebook This is one of the most popular state parks in Idaho and while there is plenty to keep you busy here, check out the Tree-to-Tree Adventure Park, with zipline and rope courses for both adults and children.

Of course, no matter what your plans are during a visit to Lake Pend Oreille, give yourself plenty of time to just sit back and admire the views. While this lake is the largest and deepest in the state, it is also surrounded by three major mountain ranges in the northern Rocky Mountains.

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And don’t be surprised if you see all types of wildlife, particularly various types of birds like ospreys, hawks, swans, eagles, geese, ducks, and more.

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While Lake Pend Oreille may not be bottomless, it’s still fun (or a little frightening!) to imagine it is while out on the water. But regardless, this lake is still one that you need to check out for yourself. Who knows … it may become your new favorite outdoor destination.

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Have you been to Lake Pend Oreille? Did you know it was one of the deepest lakes in the entire country? We’d love to hear your thoughts in the comments! If you are planning a visit to this lake, book a stay at this remarkable three-story treehouse that is located right on the shore.

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United States Navy, John F. Williams/Wikimedia Commons

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This is one of the most popular state parks in Idaho and while there is plenty to keep you busy here, check out the Tree-to-Tree Adventure Park, with zipline and rope courses for both adults and children.

kreulen/iStock Via Getty Images Plus

Stan Petersen / 500px Via Getty Images

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Address: Lake Pend Oreille, Idaho, USA