Perhaps the best-kept secret of our National Parks is the underwater realm that they include: millions of acres of submerged lands, only a fraction of which have been explored by divers.

From the geysers on the bottom of Yellowstone Lake and the coral reefs of the Dry Tortugas, to steamers sunk in the frigid waters of Isle Royale in Lake Superior and the kelp forests of the Channel Islands, the National Parks have much to offer recreational divers.

Diving in the Parks will highlight some 60 areas within the National Parks with underwater resources of interest to divers.