| State: | WY |
| Type: | WY |
| Route: | 789 |
| Alternate Name: | Canada to Mexico Highway |
| Map Custom: | yes |
| Map Notes: | WYO 789 highlighted in red |
| Length Mi: | 407.14 |
| Direction A: | South |
| Terminus A: | at Colorado state line near Baggs |
| Junction: | |
| Direction B: | North |
| Terminus B: | at the Montana state line north of Frannie |
| Counties: | Carbon, Sweetwater, Natrona, Fremont, Hot Springs, Washakie, Big Horn |
| Previous Type: | WY |
| Previous Route: | 585 |
| Next Type: | WY |
| Next Route: | 10 |
Wyoming Highway 789 (WYO 789) is a 407adj=midNaNadj=mid state highway in the U.S. state of Wyoming. WYO 789 travels south-to-north from the Colorado state line to the Montana state line. For most of its length, it is concurrent with other routes. It was the path of a formerly-proposed U.S. Route 789 that was canceled.
WYO 789 begins at the Colorado state line just south of Baggs. It travels north for about 4miles to Baggs. After Baggs, it continues north for about 45miles until it reaches the county line.
After crossing the county line, WYO 789 travels north for about 6miles where it reaches exit 187 of I-80/US 30. WYO 789 joins I-80/US 30 eastbound.
I-80/US 30/WYO 789 re-enter Carbon County. Just west of Rawlins, WYO 789 leaves at exit 211, joining I-80 Bus./US 30 Bus. through Rawlins. North of town, WYO 789 intersects US 287 and travels concurrent with it north for 50miles to the county line, after which it passes through Natrona County for about 2miles.
US 287/WYO 789 continue in a northwest direction, passing through the towns of Jeffrey City and Sweetwater Station. About 40miles from Sweetwater Station, US 287/WYO 789 enter Lander. WYO 789 splits from US 287 here and continues northeast for 24miles, alone, to Riverton. WYO 789 joins US 26 until they reach Shoshoni. Here, US 26/WYO 789 intersect US 20 where WYO 789 continues north with US 20 west.
US 20/WYO 789 continue through the Wind River Canyon into Thermopolis. From there, the highway veers off in a northeasterly direction into Washakie County. From the Washakie county line, the highway travels approximately 21miles before crossing the Big Horn River into Worland where it joins US 16/US 20.
Upon crossing into Big Horn County, US 16/US 20/WYO 789 veer back to the northwest and cross back over the Big Horn River after reaching Manderson. It continues on 20miles to the north through Basin and Greybull. Upon reaching Greybull, US 16/US 20/WYO 789 head west and join US 14 for about 5miles.
At that point, WYO 789 separates from the concurrency of US 14/US 16/US 20 and returns to its northern path along with US 310 for about 28miles to the town of Lovell. For about 3miles, US 310/WYO 789 travels west along US 14 Alt. US 310/WYO 789 then turn north for about 3miles to Cowley and then head west about 7miles to Deaver.
From Deaver, US 310/WYO 789 travel about 6miles north to Frannie, where they straddle the boundary between Big Horn County and Park County. Just to the north of Frannie, US 310/WYO 789 bends slightly to the west, so that the road is actually inside Park County by about 400 feet before reaching the Montana state line. At the state line, WYO 789 ends, while US 310 continues north.
| Country: | USA |
| Type: | US 1961 |
| Route: | 789 |
| Location: | Nogales, Arizona, to Sweet Grass, Montana |
| Formed: | November 20, 1950 |
| Decommissioned: | October 14, 1952 |
WYO 789 was part of a 1950s proposal for a border-to-border U.S. Route 789 that would have traveled from Nogales, Arizona, to Sweet Grass, Montana. After the US 789 proposal was rejected by AASHTO on 14 October 1952,[1] US 789 became part of a series of state highways numbered 789 traveling along the proposed route. Wyoming, however, was the only state that actually applied the number exclusively to existing highways (but only in some sections), whereas the other states simply added a concurrent SR 789 over existing highways. Because of this, all the states except Wyoming eventually deleted the designation and removed the signs.