Lake Pend Oreille

Located in the northern ID Panhandle, this is the largest lake in the Idaho and the 38th-largest lake by area in the country, with a surface area of 380 km2. It's 69 kilometers long, and 351 m deep in some regions, making it the 5th-deepest in the nation and having a volume of 54 km3. The lake is fed by the Clark Fork River & the Pack River, and drains into the Pend Oreille River, as well as subsurfacely into the Spokane Valley–Rathdrum Prairie Aquifer. It's surrounded by national forests and a few small towns, with the largest population on the lake being Sandpoint. The majority of the shoreline is non-populated and all but the southern tip of the lake is in Bonner County. The southern tip is in Kootenai County and is home to Farragut State Park, FKA the Farragut Naval Training Station during WW2, of which a small part is still active and conducts Navy acoustic underwater submarine research.