WyoHistory.org

The Online Encyclopedia of Wyoming History

Tri-Territory Historic Site

Tri-Territory Historic Site

With a stone monument and four flagpoles, the site marks the spot where the Louisiana Purchase, the Oregon Country and Mexico once intersected. From Rock Springs, follow State Highway 191 north for 10 miles. Go 29 miles northeast on Sweetwater County Road 4-17. Then go north on County Road 4-83 3.5 miles, and north on BLM Road 4102 3.5 miles up a steep hill to the site. County roads are gravel; travel is safest in summer in dry weather.