The Sixth principal meridian was used to survey several states that were acquired as part of the Louisiana Purchase. The meridian was established in 1855 in order to survey the newly created territories of Nebraska and Kansas. The meridian's southern terminus is at the Kansas-Oklahoma state border, and its northern terminus is at the Nebraska-South Dakota state border. Survey townships were run both east and west of the Sixth Principal meridian. Surveyors ran a principal base line westward where 40° of latitude met the Missouri River. This base line eventually became the state line between Nebraska and Kansas. Ranges run north and south from this base line. The initial point for the Sixth principal meridian surveys lies on the Nebraska-Kansas state border at 40°N latitude, 97°22'08"W longitude.
