South Dakota Highway 42

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Highway 42
Route of SD 42 (in red)
Route information
Maintained by SDDOT
Length	71.973 mi[1] (115.829 km)
Western segment
Length	5.870 mi (9.447 km)
West end	US 281 in Aurora County
East end	Aurora–Davison county line
Central segment
Length	59.231 mi (95.323 km)
West end	SD 37 west of Ethan
Major intersections	US 81 in McCook County
East end	Sioux Falls
Eastern segment
Length	6.872 mi (11.059 km)
West end	Six Mile Road in Sioux Falls
East end	Iowa 9 west of Benclare
Location
Country	United States
State	South Dakota
Counties	Aurora Davison Hanson McCook Minnehaha
Highway system
South Dakota State Trunk Highway System Interstate US State
← SD 41 → SD 43

South Dakota Highway 42 (SD 42) is a segmented state highway in southeastern South Dakota, United States. The first segment is a six-mile-long (9.7 km) highway in Aurora County. The second and longest is 60 miles (97 km) long and connects Ethan and Sioux Falls. The final segment connects Sioux Falls to Iowa Highway 9 southeast of Rowena.