Union Pass between Pinedale and Dubois, Wyoming

A monument on top marks the transition on the Continental Divide from the Wind River drainage to the Green River drainage. However, the same area also marks the transition to the Snake River drainage making this place the headwaters of the three major river systems (Green/Colorado, Snake/Columbia, and Wind River/Missouri) of the western United States. The central location and relatively easy transitions from any of the three drainages to the others has made it an important spot thousands of years. Besides some roads, the area is probably much the way it has been for hundreds of years.

Union Pass

At Union Pass a maze of mountain ranges and water courses which had sometimes baffled and repulsed them-aboriginal hunters, mountain men, fur traders and far-ranging explorers have, each in his time, found the key to a geographic conundrum. For them that conundrum had been a far more perplexing problem than such an ordinary task as negotiating the crossing, however torturous, of an unexplored pass occurring along the uncomplicated divide of an unconnected mountain chain.

Hereabouts the Continental Divide is a tricky, triple phenomenon wherein the unguided seeker of a crossing might find the right approach and still arrive at the wrong ending. In North America there are seven river systems that can be cited as truly continental in scope but only in this vicinity and at one other place do as many as three of them head against a common divide. Indians called this region the Land of Many Rivers and mountain men named the pass Union, thereby both—once again-proving themselves gifted practitioners of nomenclature.

Union Pass Kiosk on US-26 between Dubois & Moran Junction, Wyoming

Union Pass is surrounded by an extensive, rolling, mountain-top terrain wherein elevations vary between nine and ten thousand feet and interspersed water courses deceptively twist and turn as if undetermined betwixt an Atlantic or a Pacific destination. This mountain expanse might be visualized as a rounded hub in the center of which, like an axle’s spindle, fits the pass. Out from this hub radiate three spokes, each one climbing and broadening into mighty mountain ranges-southeasterly the Wind Rivers, southwesterly the Gros Ventres and northerly, extending far into Montana, the Absarokas.

The Rendezvous
Twelve thousand foot mountain plateaus dominating this view of Green River and Snake River headwaters seemingly provide a southwesterly buttress for loftier peaks forming the core of the Wind River Range. Beyond them it is 43 miles from Union Pass to where confluence of the Green and its Horse Creek tributary marks the most famed of several “rendezvous” grounds relating to that epoch in American history known as the Rocky Mountain Fur Trade.

“Rendezvous”, defined as a trade fair in wilderness surroundings, was held in diverse locations throughout the Central Rocky Mountain region. It required spacious, grassy environs for grazing thousands of horses, raising hundreds of trapper and Indian lodges and for horse races and other spectacles exuberantly staged by mountain men and Indians then relaxed from vigilance against dangers which otherwise permitted no unguarded carrousels. A favorite area for “rendezvous” was along the Green, recognized for producing the primest beaver peltry, and for conveniently straddling the South Pass logistic route utilized for transport of trade goods and furs between St. Louis and the mountains. On the Green the finest “rendezvous” grounds—rendered especially famous through Alfred Jacob Miller’s paintings of the 1837 scene—were those at Horse Creek.

Depending on arrival of St. Louis supply caravans, ‘rendezvous” usually extended through early July. At the close of revels—leaving many mountain men deeply in debt—there remained up to two months before prime furs signaled the start of fall hunting. The intervening time was pleasantly occupied in traveling and exploring high mountain terrain; then trails around Union Pass were furrowed by Indian travois only to be leveled again by the beating hoofs of the trapper’s pack trains.

Here a raindrop splits into thirds, the three tiny driblets destined to wend their separate ways along continuously diverging channels to the oceans of the world. One driblet arrives in the Gulf of Mexico, 3,000 miles distant by way of Jakeys Fork, Wind River, Bighorn, Yellowstone, Missouri, and Mississippi; another joins currents running 1,400 miles to the Pacific through Fish Creek, the Gros Ventre, Snake and Columbia; the final one descends more than 1,300 miles to the Gulf of California; via Roaring Fork, Green River and the Colorado.

Three different mountain ranges rise in the distance to heights of 13,000 feet or more. They are the Wind River and Gross Ventre Ranges to the southwest and the Absaroka Range to the north. The main mountain passes visible from the pass are Union Peak to the east, Triple Divide Peak to the southeast, rims of the Roaring Fork Plateau to the south and parts of Ram's Horn to the north.

Elevation: 9,210 Feet

Distance: 15 Miles

Directions: From Dubois, Union Pass Road is accessible by traveling nine miles northwest Dubois on US 26-287 to the marked Union Pass. Follow Union Pass road 15 miles to an interpretive site complete with a short nature walk that explains in part the surrounding area.