End of the Line on the Dakotas’ Border
The weather was bright and hot when an expert U.S. surveyor and his team finished marking the North Dakota-South Dakota border on this date in 1892. Split along the seventh standard parallel, the Dakotas are marked every half-mile by quartzite monuments. Over 700 originally lined the boundary. Only a few hundred remain today.
Surveyor Charles Bates won the bid to mark the border in 1891. Twenty-five thousand dollars were appropriated by Congress for the project. Bates’ bid was $21,300. He began where the Dakotas meet Minnesota at the Bois de Sioux River.
Bates and eight assistants worked west that fall, hampered by bad weather, insects and the changing topography. They stopped for the winter with Monument 190, set just east of the Missouri River.
Bates and a larger team began work west of the Big Muddy the following March. The west river seventh standard parallel had never been surveyed, so additional work was required. Bates’ crew moved with difficultly through the rough terrain, which included the badlands. The heat soared in summer, but by early August the crew finally neared the end of the boundary at Montana.
At a spot on the rolling prairie, over 25 miles from the closest town of Marmarth, Bates and his workers set the Terminal Monument. It’s marked with TM on its east side. It also includes the boundary states’ initials, the exact length of the border, and Bates’ name.
A few hundred Dakota markers are estimated to be around today, but hundreds of others have fallen to farming, thieves or road construction. Dozens have been reutilized as birdbaths, foundation stones, fireplace mantles and lawn ornaments. Removing or possessing a Dakota marker violates several federal laws.
Few boundaries in the world are as distinctly marked at such a length—a little over 360 miles. Many Dakota markers can still be seen today along the back roads of the border. And each fall there’s a reminder of the markers’ legacy as NDSU and SDSU battle each other in football for the prized Dakota Marker trophy, a granite replica of the 800-pound pieces of quartzite that dot the Dakota prairie.
Dakota Datebook written by Jack Dura
Associated Press. (2007, June 4). Officials seek return of South Dakota-North Dakota border markers. Rapid City Journal. Retrieved from:
Iseminger, G. L. (2007). The quartzite border: Surveying and marking the North Dakota-South Dakota boundary 1891-1892 (2nd ed.). Sioux Falls, SD: The Center for Western Studies.