The Green River defies gravity: it flows through 99 miles of mountains thanks to movements hidden beneath the surface.

The Missouri River—not the Mississippi—is the longest river in the U.S. Discover its 2,341-mile journey and its vital role in ...

The United States has quite a formidable landmass, with thousands of square miles stretched between two oceans, mountains, deserts, great plains, and everything in between. With such a large area, the ...

CIÉNEGA DE SANTA CLARA, Mexico — The rusty observation tower at the edge of this wastewater-fed marsh offers an osprey-eye view of two possible futures for the parched and overworked Colorado River.