Congressional Land Survey System
The Congressional survey system is based on 49 meridian systems distributed across the United States. It encompasses all states except those in the Carter, N.E. and Texas survey systems. Some meridian systems are wholly enclosed within state boundaries while other meridian systems span multiple states. Each meridian system is composed of a north-south oriented principle meridian and a bisecting east-west base meridian. Within the meridian system the land is divided into 36 square mile rectangular sections of land, 6 miles on a side, called a township. For simplicity it is assumed that townships are always square and of 36 square miles in size but this is not always true. Each township is divided into 36 1 square mile sections. Sections are numbered beginning in the northeast corner of the township and increasing in value to the west to 6 and then dropping down a row and numbering west to east and continuing in this serpentine pattern until all sections are numbered. Townships are numbered north or south relative to the base meridian while ranges are numbered east or west relative to the principle meridian. T.1S, R.3E is the 1st row of townships south of the base meridian and the 3rd column of ranges east of the principle meridian. The intersection of the east-west row with the north-south column uniquely identifies T.1S, R.3E.