North Dakota Century Code Title 11. Counties § 11-01-44. Sioux County

Beginning at the southwest corner of township one hundred twenty-nine north, range ninety west of the fifth principal meridian, a point on the seventh standard parallel; thence east along the seventh standard parallel to the main channel of the Missouri River; thence in a northerly direction along the main channel of the Missouri River to the point where the main channel of the Cannonball River intersects the main channel of the Missouri River; thence in a southwesterly direction along the main channel of the Cannonball River and the South Fork of the Cannonball River to the point where the line between ranges ninety and ninety-one west intersects the main channel of the South Fork of the Cannonball River; thence south along the line between ranges ninety and ninety-one west to the point of beginning.