# Wisconsin Highway 15

State Trunk Highway 15 (STH-15, commonly known as Highway 15 or WIS 15) is a 14.8-mile (23.8 km) state highway in Outagamie County in the US state of Wisconsin that runs east–west and provides a shortcut to Appleton from U.S. Highway 45 (US 45) for travelers inbound from points north and west. Most of WIS 15 was once part of US 45, which was redirected south of New London to bypass Appleton and provide direct access to Oshkosh and points south.

## Route description

WIS 15 begins at the junction of US 45 and County Trunk Highway T (CTH-T) in the Town of Hortonia (just southeast of New London) as a four-lane divided expressway and heads southeast to Hortonville where the route runs around the northern edge of the village. Access to the center of Hortenville is provided with roundabouts at either end of the village. The route then continues southeast into Greenville. The highway intersects WIS 76 in Greenville then continues southeast for one mile (one point six kilometres) before turning east at the junction with CTH-CB. WIS 15 then junctions with Interstate 41 (I-41) where it ends and Northland Avenue and CTH-OO begin in the Town of Grand Chute, just northwest of Appleton. WIS 15 provides access to Neuroscience Group Field at Fox Cities Stadium.

## History

This is the third iteration of the route number. The first iteration followed present day US 41 from the Illinois border to Marinette via Milwaukee, Fond du Lac, Appleton and Green Bay. The second is the more well-known alignment following the present day I-43 from the Hale Interchange in Milwaukee to I-90 in Beloit as the Rock Freeway. From the Hale Interchange, this iteration followed I-894 northward then turned east onto National Avenue and ended in downtown Milwaukee.
Previously, the current WIS 15 route was US 45, which turned south at its intersection with WIS 76. The later highway continued straight on to intersect with Wisconsin Avenue (then US 10) at the north entrance road to the Fox River Mall in Appleton. The road was realigned as part of a large project that realigned US 10 and US 45. Essentially, the road south of Greenville became an extension of WIS 76, and WIS 15 is now the sole route number on the current stretch.
Between 2022 and 2024, the Wisconsin Department of Transportation (WisDOT) completed an expansion and reconstruction project between US 45 in New London to WIS 76 in Greenville. The entire length of WIS 15 was converted into a four-lane divided expressway as part of the project which was previously a two-lane undivided highway. Also included was the construction of a bypass section of Hortonville which completed in 2023; the previous alignment through Hortonville is now designated as an extension of CTH-JJ.

## Future

Between 2024 and 2026, the highway's interchange with I-41 in Grand Chute will be reconstructed as a part of the wider Appleton area I-41/US 41 expansion project.

## Major intersections

The entire route is in Outagamie County.
| Location | mi | km | Destinations | Notes |
| Town of Hortonia | 0.00 | 0.00 | US 45 – Appleton, Clintonville, Marion, Antigo, Oshkosh Bus. US 45 / CTH-T – Appleton | Western end of CTH-T concurrency; roadway continues as Bus. US 45/CTH-T |
| Town of Hortonia | 3.18 | 5.12 | CTH-T south (Givens Road) – Dale CTH-JJ east (West Main Street) – Hortonville | Eastern end of CTH-T concurrency |
| Hortonville | 5.16 | 8.30 | CTH-M (Dash Street) – Medina, Winchester | Converted to overpass |
| Town of Greenville | 7.23 | 11.64 | CTH-JJ (West Broadway Drive) | |
| Community of Greenville | 10.98 | 17.67 | WIS 76 (Municipal Drive) – Oshkosh, Shiocton | |
| Town of Greenville | 12.75 | 20.52 | CTH-CB (Greenville Drive) – Appleton International Airport | |
| Town of Grand Chute | 14.8 | 23.8 | I-41 / US 41 – Milwaukee, Green Bay CTH-OO east (West Northland Avenue) – Appleton, Little Chute | Roadway continues as CTH-OO |
| 1.000 mi = 1.609 km; 1.000 km = 0.621 mi Closed/former Concurrency terminus |||||