Interstate 29 (I-29) is an Interstate Highway in the Midwestern United States. I-29 runs from Kansas City, Missouri, at a junction with I-35 and I-70, to the Canada–US border near Pembina, North Dakota, where it connects with Manitoba Provincial Trunk Highway 75 (PTH 75), which continues on to Winnipeg. The road follows the course of three major rivers, all of which form the borders of US states. The southern portion of I-29 closely parallels the Missouri River from Kansas City northward to Sioux City, Iowa, where it crosses and then parallels the Big Sioux River. For the northern third of the highway, it closely follows the Red River of the North. The major cities that I-29 connects to includes Council Bluffs, Iowa; Sioux Falls, South Dakota; Fargo, North Dakota; and Grand Forks, North Dakota.
U.S. Highway 16 (US 16) is an east–west United States Numbered Highway between Rapid City, South Dakota, and Yellowstone National Park in Wyoming. The highway's eastern terminus is at a junction with Interstate 90 (I-90)/US 14, concurrent with I-190, in Rapid City. The western terminus is the east entrance to Yellowstone National Park, concurrent with US 14 and US 20. US 16 used to extend all the way to Michigan but has been truncated in favor of I-90 and I-96.
U.S. Highway 18 (US 18) is an east–west United States Numbered Highway in the Midwestern United States. The western terminus is in Orin, Wyoming, at an interchange with Interstate 25 (I-25). Its eastern terminus is in downtown Milwaukee, Wisconsin. However, US 18 runs concurrent with other U.S. Highways from its western terminus to Mule Creek Junction, Wyoming. US 18 is one of the original U.S. Highways of 1926. The US 18 designation was originally proposed for a road in Michigan from Grand Haven east to Detroit. This roadway was eventually designated as US 16.
South Dakota Highway 115 is a 40-mile (64 km) state highway in Lincoln and Minnehaha countess in South Dakota, United States, that was created from the routing of US 77, "Old 77", when its alignment was moved west to become Interstate 29 around 1980 and SD 15's route from US 18 to Sioux Falls. SD 115 routes from its intersection with US 18 about 13 miles (21 km) south of Sioux Falls to Interstate 29 three miles west of Dell Rapids. It is about 40.5 miles (65.2 km) in length.
South Dakota Highway 43 (SD 43) is a 1.131-mile-long (1.820 km) state highway that exists entirely in the southern part of Gregory County in the southern part of the U.S. state of South Dakota. It begins as an extension of Nebraska Highway 11 (N-11) at the Nebraska state line south of Fairfax. It travels northwest to an intersection with U.S. Route 18 (US 18) south-southwest of the town.
South Dakota Highway 45 is a state highway that runs north to south across much of central South Dakota, United States. The northern terminus is at the North Dakota border as a continuation of North Dakota Highway 3, and runs south to South Dakota Highway 44 at Platte. It is 198 miles (319 km) in length.
South Dakota Highway 47 is a state route that runs north to south across the central portion of South Dakota. It begins at an unnumbered highway at the North Dakota border north of Eureka, and ends at the Nebraska border, where it becomes Nebraska Highway 137. It is just under 241 miles (388 km) in length.
South Dakota Highway 48 is a 12.462-mile (20.056 km) state highway in Union County, South Dakota, United States, that begins at Interstate 29, about 2.5 miles (4.0 km) west of Spink, and becomes Big Sioux River Road, formerly Iowa Highway 403, northwest of Akron, Iowa.
South Dakota Highway 22 (SD 22) is a 48.546-mile-long (78.127 km) state highway in Hamlin and Deuel counties in South Dakota, United States. It connects Hazel and Clear Lake.
South Dakota Highway 53 is a state route that runs north to south across south central South Dakota. It consists of two separate segments:
South Dakota Highway 15 (SD 15) is a 67.562-mile-long (108.730 km) state highway in the northeastern South Dakota, United States. It connects Clear Lake, Milbank, and Wilmot.
South Dakota Highway 30 (SD 30) is a 17.077-mile-long (27.483 km) state highway in the east-central part of the U.S. state of South Dakota. It connects the north-central part of Brookings with the northeastern part of it.
South Dakota Highway 34 is a state route that runs parallel to Interstate 90 across the entire state of South Dakota. It begins at the Wyoming border west of Belle Fourche, as a continuation of Wyoming Highway 24 (WYO 24). The eastern terminus is at the Minnesota border east of Egan, or southwest of Airlie, Minnesota, where it continues as Minnesota State Highway 30 (MN 30). It is just over 419 miles (674 km) in length, making it the longest state highway in South Dakota.
South Dakota Highway 73 is a state route that runs across western South Dakota. It begins at the Nebraska border, north of Merriman, Nebraska, as a continuation of Nebraska Highway 61. It runs to the North Dakota border, where it continues as North Dakota Highway 49. It is just more than 255 miles (410 km) in length.
South Dakota Highway 11 (SD 11) is a 77.724-mile (125.085 km) state highway in eastern South Dakota, United States. It connects the northern part of the Sioux City metropolitan area with the Sioux Falls metropolitan area.
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.
U.S. Highway 20 (US-20) is a part of the United States Numbered Highway System that runs for 3,365 miles (5,415 km) from Newport, Oregon, to Boston, Massachusetts. Within the state of Nebraska, it is a state highway that begins on the Wyoming–Nebraska state line west of Harrison near the Niobrara River and runs to the Nebraska–Iowa state line in South Sioux City. Throughout its 431.60-mile (694.59 km) length, the route passes through a diverse range of landscapes, including bluffs and escarpments in the Nebraska Panhandle, the Sandhills in the northern part of the state, and rolling hills and plains as the highway approaches the Missouri River valley south of Sioux City, Iowa. Throughout its length, US-20 is a two-lane highway with the exception of the easternmost 8.45 miles (13.60 km), which is a four-lane divided highway, the last 3.21 miles (5.17 km) of which is concurrent with Interstate 129 (I-129). The 197 miles (317 km) between the Wyoming border and Valentine is designated as the Bridges to Buttes Byway, one of nine scenic byways in the state of Nebraska.
Interstate 29 (I-29) is a north–south Interstate Highway in the midwestern United States. In the state of South Dakota, I-29 traverses on the eastern side of the state from the Iowa border near Sioux City to the North Dakota border near New Effington. On its route, I-29 passes through western portions of Sioux Falls, the state's largest city. It travels 252.5 miles (406.4 km) in the state, the longest stretch of any of the four states through which it passes. I-229, the highway's lone auxiliary route in South Dakota, serves as a bypass around southern and eastern Sioux Falls.
U.S. Highway 16 (US 16) is a 69-mile-long (111 km) east–west United States Numbered Highway in the western part of the state of South Dakota. It travels between Yellowstone National Park near Newcastle, Wyoming and Interstate 90 (I-90) in Rapid City
Lewis and Clark Trail 
Native American Scenic Byway 
SD 34 east of Fort Thompson 
Iowa 3 near Richland
