What is the primary survey line that runs from East to West called?

The primary survey line that runs from East to West is known as a base line. A base line serves as a fundamental reference line for land surveyors, playing a crucial role in the rectangular survey system, also known as the Public Land Survey System (PLSS). This system divides land into townships and sections, making it easier to locate and describe parcels of land.

When working with the rectangular survey system, the base line functions in conjunction with principal meridians, which are the primary survey lines running from North to South. While latitude lines also run parallel to the equator and are utilized for mapping, they are not specific to the land survey system framework and do not serve the same purpose as a base line. Longitude lines, on the other hand, run from pole to pole and are similarly distinct from the context of surveying land use in the United States.

Understanding the role of the base line is essential for comprehending how land is organized and described in a systematic manner.