State Trunk Highway 42 (often called Highway 42, STH-42 or WIS 42) is a state highway in the U.S. state of Wisconsin. It runs for north–south in northeast Wisconsin from Sheboygan to the ferry dock in Northport. Much of the highway is part of the Lake Michigan Circle Tour from the eastern junction with U.S. Highway 10 (US 10) in Manitowoc to its junction with WIS 57 in Sister Bay. WIS 42 parallels I-43 from Sheboygan to Manitowoc, and parallels WIS 57 throughout much of the route, particularly from Manitowoc to Sturgeon Bay, meeting the northern terminus of WIS 57 in Sister Bay.
Route description
Sheboygan to Manitowoc
WIS 42 begins at the intersection of North 14th Street and Erie Avenue (also known as Kohler Memorial Drive) in downtown Sheboygan, a block north of the bridge crossing the Sheboygan River. The intersection is the terminus of two other state highways, WIS 23 and WIS 28.
WIS 42 follows North 14th Street to Calumet Drive, which heads out of the city in a northwesterly direction to its interchange with Interstate 43 (I-43) at exit 128 which has four roundabouts within a mile; two controlling freeway access, a retail development with Walmart and Menards at Vanguard Drive, and then CTH-Y. The route continues to the northwest into the city of Howards Grove past Howards Grove High School, where it becomes Madison Avenue. Because there are only two exits in the between WIS 42's junctions with I-43 in Sheboygan and Manitowoc, it also serves as the state-designated Alternate I-43 (along with the roads from those two exits from WIS 42) when road incidents close I-43 proper.
At the intersection of Madison Avenue and South Wisconsin Drive, WIS 42 and WIS 32 meet. WIS 32 continues to the northwest on Madison Avenue, while WIS 42 turns north on Wisconsin Drive. WIS 42 continues north out of Howards Grove into Manitowoc County. While in southern Manitowoc County, WIS 42 intersects County Trunk Highway XX (CTH-XX), which leads east to I-43 and Cleveland, carrying it for about a mile before CTH-XX heads west towards Kiel in the community of Meeme. It intersects with CTH-C in the town of Newton, also leading east to I-43 while west towards St. Nazianz.
Manitowoc to Sturgeon Bay
WIS 42 continues to the north towards the city of Manitowoc, where it intersects US 151 (Calumet Avenue) just west of I-43. Turning east, WIS 42 runs concurrently with US 151 for about a quarter mile (0.4 km) before US 151 ends at I-43. WIS 42 then travels on Calumet Avenue into Manitowoc's business district where it intersects with US 10 twice before leaving US 10 and turning east onto Waldo Boulevard for Lake Michigan and Two Rivers. Prior to 2022, WIS 42 turned north onto I-43 at I-43 Exit 149 for Calumet Avenue and exited the interstate with US 10 onto Waldo Boulevard.
Crossing the West Twin River near its confluence with the East Twin River just south of downtown Two Rivers, WIS 42 becomes Washington Street. Two blocks north, it meets the eastern terminus of WIS 310 at 16th Street. Six blocks north, it meets the eastern terminus of WIS 147 at 22nd Street.
WIS 42 turns to the east on 22nd Street and crosses over the East Twin River, then turns north on Lincoln Avenue. WIS 42 and WIS 147 are the only two state highways that cross both branches of the Twin Rivers, though WIS 147 does not cross the West Twin River until about a mile east of its terminus with I-43 near Maribel.
WIS 42 continues to the north, running roughly parallel to the Lake Michigan shoreline into Kewaunee County. Just south of the city of Kewaunee, WIS 42 turns east on Krok Road to Lakeshore Drive, where it turns north and heads into the city as Milwaukee Street. In downtown Kewaunee, WIS 42 meets the eastern terminus of another state highway, WIS 29. WIS 42 becomes Main Street after crossing the Kewaunee River and continues north out of the city.
In the unincorporated town of Alaska, WIS 42 again turns east towards Lake Michigan to follow the shoreline into Algoma as Lake Street. In downtown Algoma, WIS 42 turns north onto 4th Street and crosses the Ahnapee River. On the north bank of the river, WIS 42 turns northwest onto North Water Street and follows the river in a northerly direction to Forestville in Door County, where it becomes Forestville Avenue.
Because of the geographical features and terrain of Door County, WIS 42 makes many abrupt turns as it nears its northern terminus at the tip of the Door Peninsula.