Baseline (surveying)

Baseline (surveying)

In the United States Public Land Survey System, a baseline is the principal east-west line upon which all rectangular surveys in a defined area are based. The baseline meets its corresponding meridian at the point of origin, or initial point, for the land survey. For example, the baseline for Nebraska and Kansas is shared as the border for both states, at the 40th parallel north.

More specifically a baseline may be the line that divides a survey township between north and south.

Often, a baseline is marked by other features such as a road or boundary between counties.