The Continental Divide is a geological and hydrological boundary that defines the direction of water flow across the American continent. In the high-elevation landscape of the American West, this ridge acts as a seam, directing precipitation into vast, separate drainage systems. Specifically, in Wyoming, the Divide determines whether a raindrop will ultimately flow toward the Pacific Ocean or be routed into the Atlantic Ocean and Gulf of Mexico watershed. This immense boundary traces a complex, often rugged, path through the state’s mountains and plateaus.
The Path Through Wyoming’s Mountain Ranges
The Continental Divide enters Wyoming from the south near the Sierra Madre Mountains and proceeds northward. It tracks a generally north-south course, forming the spine of the state’s most formidable mountain chains. The Divide is prominently defined by the crest of the Wind River Range, which features Wyoming’s tallest peaks. This section is characterized by alpine terrain, glaciers, and elevations that frequently exceed 13,000 feet, including Gannett Peak, the highest point in the state.
The path through the Wind River Range is a continuous, clearly defined ridgeline, separating the headwaters of the Colorado River system on the west from the Missouri River tributaries on the east. The Divide eventually drops significantly at the historic South Pass, a broad, relatively gentle depression that served as a low-elevation migration corridor for pioneers. This pass, situated at an elevation of 7,550 feet, represents one of the lowest crossings in the Rocky Mountain chain.
From South Pass, the Divide briefly re-ascends before encountering a major anomaly in the south-central part of the state, causing it to split. Further north, the main line passes through the Teton Wilderness and crosses US Highway 26/287 at Togwotee Pass (9,658 feet). It then continues into the geothermal regions of Yellowstone National Park, marked by high plateaus and volcanic features before exiting the state near the Idaho border.
The Great Divide Basin Phenomenon
The most unusual feature of the Continental Divide in Wyoming is the Great Divide Basin (GDB), a high-desert region of approximately 4,000 square miles. This basin is an endorheic system, meaning it is a closed drainage area with no outlet to the ocean. Instead of following a single mountain crest, the Continental Divide temporarily splits into two separate boundary lines that encircle the basin.
Precipitation that falls inside the basin collects in ephemeral lakes or sinks into the ground. The water dissipates through evaporation or infiltration rather than contributing to any major river system. The arid landscape of the GDB, often called the Red Desert, is characterized by sagebrush steppe and sand dunes.
The western boundary of the split Divide directs water toward the Green River, a tributary of the Colorado River that flows to the Pacific Ocean. Conversely, the eastern boundary routes water into the North Platte River system, which drains toward the Atlantic Ocean via the Gulf of Mexico.
Crossing the Divide Practical Travel Information
Travelers can experience the Continental Divide in Wyoming using major transportation corridors. The most notable crossing for motorists is along Interstate 80 (I-80) in south-central Wyoming, which passes directly through the Great Divide Basin. Because the Divide splits to form the basin, drivers on I-80 cross the hydrological boundary twice within a 50-mile stretch near Rawlins.
US Highway 26/287 crosses the Divide at Togwotee Pass, offering dramatic views of the Teton and Wind River Ranges. US Highway 287 also crosses the Divide near South Pass, providing a glimpse of the historic pioneer trail corridor. These paved routes are accessible to standard vehicles throughout the non-winter months, though high-altitude passes are subject to seasonal closures.
Recreational adventurers can follow the Continental Divide National Scenic Trail (CDT), a non-motorized route spanning approximately 550 miles across Wyoming. The CDT closely traces the Divide’s geographical path, guiding hikers and horseback riders through the rugged Wind River Range wilderness. The trail offers an immersive way to witness the continent’s major water boundary.