Because of the crystal-clear water, Flathead Lake in Montana seems shallow, but in reality is 370 feet in depth. jazcaball Uncategorized April 5, 2013 1 Minute did-you-kno: Source Share this: Share on X (Opens in new window) X Share on Facebook (Opens in new window) Facebook Like Loading... Related Published by jazcaball View all posts by jazcaball Published April 5, 2013