US Highway 20 (US 20) is an east–west highway in the state of

Wyoming Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south ...

. The eastern segment of US 20 in the state starts at the eastern entrance to

Yellowstone National Park Yellowstone National Park is an American national park located in the western United States, largely in the northwest corner of Wyoming and extending into Montana and Idaho. It was established by the 42nd U.S. Congress with the Yellowston ...

along with the western termini of US 14 and US 16. US 14/US 16/US 20 runs east to Greybull, where US 14 continues east and US 16/US 20 turns south; at Worland, US 16 turns east while US 20 continues south, passing through

Wind River Canyon Wind River Canyon is a scenic Wyoming canyon on the Wind River. It is located between the towns of Shoshoni and Thermopolis and is a popular stop for visitors to Yellowstone National Park. It is accessible by U.S. Highway 20 and Wyoming Highwa ...

south of

Thermopolis Thermopolis is the county seat and largest town in Hot Springs County, Wyoming, United States. As of the 2020 U.S. Census, the town population was 2,725. Thermopolis is Greek for "hot city." It is home to numerous natural hot springs, in which m ...

. US 20 joins US 26 in

Shoshoni The Shoshone or Shoshoni ( or ) are a Native American tribe with four large cultural/linguistic divisions: * Eastern Shoshone: Wyoming * Northern Shoshone: southern Idaho * Western Shoshone: Nevada, northern Utah * Goshute: western Utah, easter ...

, where it turns east and continues all the way through

Casper Casper may refer to: People * Casper (given name) * Casper (surname) * Casper (Maya ruler) (422–487?), ruler of the Mayan city of Palenque * Tok Casper, first known king of Maya city-state Quiriguá in Guatemala, ruling beginning in 426 * David ...

. From Casper, US 20/US 26 parallels

Interstate 25 Interstate 25 (I-25) is a major Interstate Highway in the western United States. It is primarily a north–south highway, serving as the main route through New Mexico, Colorado, and Wyoming. I-25 stretches from I-10 at Las Cruces, New Mexic ...

(I-25) and US 87 for , until all four link up together just southeast of Glenrock. I-25/US 20/US 26/US 87 stays combined to

Orin ORiN (Open Robot/Resource interface for the Network) is a standard network interface for FA (factory automation) systems. The Japan Robot Association proposed ORiN in 2002, and the ORiN Forum develops and maintains the ORiN standard. Background ...

, where US 20 turns east from I-25, at the western end of US 18. US 18/US 20 run concurrently from Orin to Lusk, where US 18 turns north and US 20 continues east into Nebraska.

Route description

Yellowstone National Park

Cars arriving at the East Entrance (42952890752)

Google Maps Google Maps is a web mapping platform and consumer application offered by Google. It offers satellite imagery, aerial photography, street maps, 360° interactive panoramic views of streets ( Street View), real-time traffic conditions, and rou ...

and other mapmakers may show US 20 and other U.S. Routes going through

; however, they are officially discontinuous and unsigned inside the park. Unofficially, Google Maps marks the start of the western part of US 20, along with US 191 and US 287, at the state line near

West Yellowstone, Montana West Yellowstone is a town in Gallatin County, Montana, United States, adjacent to Yellowstone National Park. The population was 1,272 at the 2020 census. West Yellowstone is served by Yellowstone Airport. It is part of the Bozeman, MT Micropoli ...

. The road parallels the Madison River until a junction with US 89. The three routes then turn south along US 89 (Grand Loop Road), paralleling the Firehole River. Past Old Faithful, the four routes curve east before reaching the West Thumb of Yellowstone Lake. While the rest of the routes turn south, US 20 travels northeast along the lake. US 20 even leaves the Grand Loop Road at an intersection midway along the lake. This intersection also marks the western "termini" of US 14 and US 16. US 20 travels through for by the time it exits the park.

Yellowstone–Nebraska state line

The eastern section of US 20 begins at the east entrance of Yellowstone National Park. US 20, along with US 14 and US 16, then meanders east along the Shoshone River, heading toward Wapiti, Buffalo Bill Reservoir, and Cody. US 14A begins at Cody and continues to follow the river, while the three head straight to Greybull. Before Greybull, however, WYO 789 joins the concurrency. At Greybull, US 14 leaves the concurrency. At this point, the concurrency parallels the Bighorn River. In Worland, US 16 turns east and leaves the concurrency. South of the Boysen Dam, the road runs along the eastern front of the Boysen Reservoir. In Shoshoni, US 20 turns east along US 26, while WYO 789 turns west along the same route. As US 20 and US 26 head toward Casper, the two routes travel along a limited-access road before traveling east along I-25 and US 87. US 20, US 26, and US 87 exit onto Beverly Street (exit 186) and travel east along Yellowstone Highway. Before reaching Glenrock, the three U.S. routes are sandwiched between the North Platte River to the north and I-25 to the south. The three routes rejoins the interstate after Glenrock. US 20 leaves the freeway at Orin; this interchange is also where US 18 begins eastward. US 87 briefly joins the concurrency before US 20 turns east away from US 18/US 85. After passing through Van Tassell, US 20 crosses the Nebraska state line.

History

U.S. Route 20 became a U.S. highway in 1926. Prior to 1940, it ended at Yellowstone National Park. In 1940, it was extended westward to Albany, Oregon; however, as U.S. routes are not formally designated in national parks such as Yellowstone, US 20 can be thought of as made up of two parts broken by Yellowstone National Park.

Major intersections

References

External links

* {{state detail page browse, type=US, route=20, state=Wyoming, statebefore=Montana, stateafter=Nebraska U.S. Highways in Wyoming

Transportation in Park County, Wyoming Transportation in Big Horn County, Wyoming Transportation in Washakie County, Wyoming Transportation in Hot Springs County, Wyoming Transportation in Fremont County, Wyoming Transportation in Natrona County, Wyoming Transportation in Converse County, Wyoming Transportation in Niobrara County, Wyoming