| State: | WI |
| Type: | WI |
| Route: | 80 |
| Map Custom: | yes |
| Map Notes: | WIS 80 highlighted in red |
| Length Mi: | 175.73 |
| Length Round: | 2 |
| Direction A: | South |
| Direction B: | North |
| Terminus A: | in Hazel Green |
| Junction: |
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| Terminus B: | in Marshfield |
| Counties: | Grant, Iowa, Richland, Vernon, Juneau, Wood |
| Previous Type: | WI |
| Previous Route: | 79 |
| Next Type: | WI |
| Next Route: | 81 |
State Trunk Highway 80 (abbreviated as Highway 80, STH-80 or WIS 80) is a state highway in the U.S. state of Wisconsin. It runs north - south in southwest and west central Wisconsin from just south of Marshfield, near the geographic center of the state to the Illinois border near Hazel Green.
WIS 80 begins at the Illinois state line as a continuation of Illinois Route 84. It enters Hazel Green, where WIS 11 joins for a few miles. North of the end of the concurrency, WIS 80 passes through Cuba City. Occasionally the highway aligns itself with the Grant-Lafayette county line. The highway enters Platteville, where it meets US 151 south of town and WIS 81 in town. As WIS 80 leaves Platteville it heads north along the Iowa-Grant county line past Livingston and into Montfort. At Montfort, the highway joins with US 18 for 8 miles before heading north from Cobb, where the land becomes more forested. WIS 80 heads through Highland. WIS 133 joins WIS 80 west for five miles before WIS 80 heads north again from Muscoda, where it crosses the Wisconsin River.
North of Muscoda, the highway passes through Richland Center and Hub City before entering Hillsboro and joins with WIS 33/WIS 82. The three-way concurrency leaves Hillsboro and enters Union Center, where WIS 33 leaves the concurrency and WIS 80/WIS 82 go north to the southern trailhead of the Elroy-Sparta State Trail, the northern trailhead of the 400 State Trail, and Elroy. In Elroy, WIS 82 leaves the concurrency with WIS 80. WIS 80 continues north and leaves the Driftless Area before entering New Lisbon. North of New Lisbon it passes the junction with Interstate 90/Interstate 94 (I-90/94). North of New Lisbon the highway passes through the center of Necedah, and the terrain is flat as it passes along the Necedah National Wildlife Refuge and enters Pittsville, where it merges with WIS 73 and heading west for 2.5 miles. As it leaves the concurrency, it runs north through the farmlands of Wood County, Wisconsin. WIS 80 ends at a roundabout junction with US 10 just south of Marshfield.[1]
WIS 80 crosses the Wisconsin River into Muscoda,[1] which bills itself as the "Morel mushroom capital of Wisconsin". WIS 133 joins WIS 80 east 5miles before WIS 80 heads south again to Highland and Cobb, where the land continues to be hilly but becomes less forested and more rolling farmland. At Cobb, WIS 80 follows US 18 west for 5miles before heading south along the Iowa–Grant county line past Livingston and into Platteville, where it meets WIS 81 in town and US 151 south of town at the freeway bypass. South of Platteville, WIS 80 occasionally aligns itself along the Grant–Lafayette county line as it heads through Cuba City and Hazel Green, where WIS 11 joins for a few miles. South of Hazel Green, WIS 80 ends at the Illinois state line, where it meets Illinois Route 84 (IL 84) NaNmiles west of the state's "Point of Beginning",[1] the location from which most public land surveys in Wisconsin originated.