County Road 42 (Dakota County, Minnesota)

County State-Aid Highway 42, usually called County Road 42, is a primary arterial highway in Dakota and Scott Counties of southeastern Minnesota. These two counties form the southernmost portion of the Twin Cities Metropolitan Area, although CSAH 42 runs across the northern reaches of the two counties. CSAH 42's easternmost terminus is in Hastings, Minnesota in Dakota County, when it meets U.S. Highway 61. Its westernmost terminus is just southeast of Shakopee, Minnesota in Scott County, where it intersects County Road 17 (Marschall Road).

Designated as a "principal arterial" highway by the Metropolitan Council, County Road 42 is supposed to have limited commercial access and signals only at one-half mile intervals. However, because it was used as a primary commercial road before its designation as a principal arterial highway, it passes directly through the downtown areas of several cities in Dakota and Scott Counties (especially Apple Valley and Burnsville in Dakota County) and in those areas it has signaled intersections at intervals as brief as 50 yards.

Most of County Road 42 is designated as part of the National Highway System. It intersects Cedar Avenue two miles south of the terminus of Highway 77, as well as Interstates 35E and 35W.