U.S. Route 20 (Wyoming)

U.S. Route 20 (Wyoming)
State	WY
Type	US
Route	20
Length mi	412.00
Established	1926
Direction a	West
Terminus a	Teton Pass
Direction b	East
Terminus b	Nebraska
Counties	Teton County, Fremont County, Hot Springs County, Washakie County, Big Horn County, Natrona County, Converse County, Goshen County, Niobrara County

U.S. Route 20 (Wyoming) is the segment of the United States Numbered Highway that traverses northern and central Wyoming from the Teton Pass area eastward to the Nebraska state line, linking mountain corridors, high plains, and municipal centers across diverse landscapes. The highway connects with major transcontinental routes and serves as a corridor for Jackson, Riverton, Shoshoni, Thermopolis, Cody area connections, and Casper-area access, while intersecting with Interstate 25, U.S. Route 26, and U.S. Route 87 in multiple locations. The route supports tourism to Grand Teton National Park, Yellowstone National Park, and regional resource transportation related to Powell and Sheridan economic activity.

Route description

From the western approaches at Teton Pass and the vicinity of Jackson Hole, the highway moves east through the town of Jackson and parallels corridors that provide access to Grand Teton National Park and Bridger–Teton National Forest. It proceeds toward Dubois and the Wind River Range, where it intersects routes serving Fremont County communities and access to Wind River Indian Reservation. East of Riverton the alignment traverses high desert and grassland toward Shoshoni and meets corridors providing access to Thermopolis and the Hot Springs County hot springs attractions. The highway continues northeast to Graybull and the Bighorn Basin, linking to routes toward Cody and Yellowstone National Park. Crossing the plains, the route passes through or near Powell and Routt-area service points before reaching the Casper metropolitan area and converging with Interstate 25 and U.S. Route 87 around Edgerton and Glenrock. Eastward from Casper it continues through Mills, Douglas in Converse County, and Lingle before exiting into Nebraska River-adjacent plains at the Nebraska line, interfacing with long-haul freight movements linked to transcontinental rail corridors and regional Wyoming Department of Transportation maintenance divisions.

History

Designated in the original 1926 United States Numbered Highways plan, the corridor evolved from wagon roads and Lincoln Highway-era alignments and drew on earlier Oregon Trail-era wagon ruts across eastern Wyoming. Early 20th-century improvements were influenced by Good Roads Movement advocates and later New Deal-era projects administered alongside Works Progress Administration undertakings that upgraded surfacing and bridges. Mid-20th-century realignments accommodated increasing automobile and truck traffic tied to expansion of Yellowstone access and resource extraction developments near Powell and energy fields in Natrona County. Interstate-era planning shifted freight patterns to Interstate 80 and Interstate 25, leaving the route focused on regional connectivity, tourism, and agricultural transport. Recent decades have seen resurfacing, safety projects, and corridor management involving the Wyoming Department of Transportation and federal programs such as the Federal Highway Administration's aid for rural roads.

Major intersections

The highway meets multiple principal corridors and municipal gateways, including junctions with U.S. Route 26 near Shoshoni, crossings of U.S. Route 89 approaches in the Jackson area, concurrency segments with U.S. Route 287 through parts of central Wyoming, and connections to U.S. Route 191 and U.S. Route 189 corridors for Wyoming/Montana/Idaho travel. It intersects Interstate 25 and U.S. Route 87 in the Casper region, connects with state routes such as Wyoming Highway 22 at Teton approaches, Wyoming Highway 789 overlaps in the Bighorn Basin region, and provides access to U.S. Route 16 toward Cody and Powell. County and local junctions include links to Hot Springs service roads and Niobrara boundary crossings toward Nebraska.

Special routes

Several auxiliary and business alignments serve municipal centers and tourist gateways, including business loops through Jackson and Riverton that preserve downtown access while mainline traffic uses bypasses, and spur connections to recreational sites such as Grand Teton National Park entrances and Bighorn Canyon National Recreation Area access roads. Short connector segments link to Yellowstone National Park approach roads and to state-maintained scenic byways that tie into the Cloud Peak Skyway and regional heritage routes commemorating Oregon Trail and Lewis and Clark Expedition waypoints.

Traffic and safety

Traffic volumes vary seasonally with heavy summer peaks from Yellowstone National Park and Grand Teton National Park visitation, winter ski traffic to Jackson Hole Mountain Resort and commercial movements linked to energy and agricultural freight. The corridor records variable crash patterns influenced by winter Teton Pass conditions, wildlife collisions in bison and elk range near Grand Teton National Park and Wind River Range migration corridors, and long-distance heavy truck interactions near Casper and Douglas. Safety initiatives have included shoulder widening, rumble strips, bridge replacements funded through Federal Highway Administration programs, and cooperative wildlife-mitigation projects with U.S. Fish and Wildlife Service and state wildlife agencies.

Future and planned improvements

Planned investments emphasize resurfacing, targeted capacity upgrades at urban approaches to Casper and Jackson, and climate-resilience measures for snow-prone passes coordinated with Federal Emergency Management Agency and Wyoming Department of Transportation grant programs. Projects under consideration include intersection redesigns near major interchanges, enhanced traveler information systems linked to National Weather Service forecast feeds, and wildlife crossing structures informed by studies from University of Wyoming researchers and conservation partners. Long-term corridor planning is influenced by regional tourism strategies tied to Yellowstone National Park stewardship, energy transport modeling involving Bureau of Land Management-administered lands, and federal surface-transportation reauthorization provisions.

Category:U.S. Highways in Wyoming