property
base line
A base line is a main imaginary east-west line used in the rectangular (government) survey system. Each base line intersects a north-south principal meridian at a defined point. Township tiers are counted north or south of the base line, while ranges are counted east or west of the principal meridian. Together they form the reference grid for legal descriptions in states that use the system.
- Exam tip
- Remember: base lines run east-west and townships are numbered north or south from them; principal meridians run north-south and ranges are numbered east or west from them.
- Example
- A legal description reading "Township 3 North" means the township lies in the third tier north of the base line.
Related terms & state variants
Sources
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Last verified: 2026-10-23