Exactly 600 miles
Minnesota. Minnesota's western border is on the entire eastern border of North Dakota and on much of the eastern border of South Dakota until it reaches the latitude that separates Minnesota from Iowa.
The US state of Montana has an eastern border with North Dakota and South Dakota.
The Black Hills are located primarily in western South Dakota and extend into eastern Wyoming. The states that border the Black Hills are South Dakota and Wyoming.
North Dakota and South Dakota border Minnesota to the east.
North Dakota shares its northern border with Saskatchewan and Manitoba, Canada. North Dakota shares its eastern border with Minnesota, its southern border with South Dakota and its western border with Montana.
US Interstate 90 passes through South Dakota from the eastern to western border. US Interstate 29 passes through South Dakota from the northern to southern border.
Nebraska has a south-western border with Colorado and eastern border with Iowa.
Minnesota is the state which is east of both North Dakota and South Dakota. Minnesota shares its western border with North Dakota and South Dakota. Minnesota is bordered on the south by Iowa and on the east by Wisconsin and Michigan. Minnesota is bordered on the north by the Canadian provinces of Manitoba and Ontario.
Both North Dakota and South Dakota share a border with Minnesota. South Dakota also shares an eastern border with Iowa.
Wyoming and Montana share South Dakota's western border.
The Mississippi River forms Iowa's eastern border, the Missouri forms the western border with Nebraska while the Big Sioux river forms the border with South Dakota.
North Dakota is near the center of US, along the northern border (which is shared with Canada). It shares its western border with Montana, its southern border with South Dakota, its eastern border with Minnesota, and its northern border with the Canadian provinces of Manitoba (to the east) and Saskatchewan (to the west).