The Duck River in Tennessee holds the distinction of being North America’s most biodiverse river. It is one of the world’s three primary centers of fish and mussel diversity, providing habitat ...

The river claims more native fish species — 128 — than any other river of its size in North America, according to the Cahaba River Society. It's also easy to access, with canoe and boat ...

Ten miles wide and about 2,400 metres deep, it is North America’s deepest river gorge (pictured) — yet the timing and mechanism of the canyon’s formation have been unclear.