Interstate 29 runs north-south through Eastern South Dakota. This is the main highway in this part of the state. In South Dakota, this has several spurs. Ranging from a loop interstate, business loops, and a downtown spur. I-29 enters South Dakota from Iowa at North Sioux City. It enters from North Dakota, near Victor. While in South Dakota, I-29 is multi-plexed several times.
I-29 is multi-plexed with... ...U.S. Rt. 18, near Worthing. ...U.S. Rt. 81, from M.P. 180, near Watertown, to the North Dakota/South Dakota State Line. Interstate 29 crosses the following interstates in South Dakota.