South Dakota Highway 19A

Highway 19
Route of SD 19 (in red)
Route information
Defined by SDCL §31-4-143
Maintained by SDDOT
Length:	98.736 mi (158.900 km)
Existed:	1926 – present
Major junctions
South end:	N-15 south of Vermillion
	US 18 near Hurley I-90 at Humboldt
North end:	SD 34 southeast of Madison
Location
Counties:	Clay, Turner, Minnehaha, Lake
Highway system
South Dakota Highways Interstate U.S. State ← US 18 SD 20 →

South Dakota Highway 19 is a state route located in east central and southeast South Dakota. It begins at the Nebraska border, as a continuation of Nebraska Highway 15. It runs northerly to South Dakota Highway 34 southeast of Madison. It is 100 miles (161 kilometers) in length.

South Dakota 19 was implemented in 1926. Its alignment has remained the same during this period, with two exceptions.

The original routing in Turner County had SD 19 go northward into Centerville, then westward to meet its present routing. Around 1950, SD 19 was rerouted to follow South Dakota Highway 46 for 6 miles (9.7 km) before heading north again, resulting in a bypass of Centerville. The original route was designated as South Dakota Highway 19A.

In Clay County, SD 19 originally ended in Vermillion, at South Dakota Highway 50. The road was extended when the Vermillion-Newcastle Bridge over the Missouri River opened up in 2001. Previously, the nearest places to cross the river were at Yankton and Sioux City, Iowa.