Baseline (surveying)

This article is about the usage in surveying. For other uses, see Baseline (disambiguation).
"Standard parallel" redirects here. Not to be confused with Standard parallel (map projections).
This BLM map depicts the principal meridians and baselines used in the survey of the United States.

In surveying, a baseline is generally a line between two points on the Earth's surface and the direction and/or distance between them.

In a triangulation network, at least one distance between two stations needs to be measured to calculate the size of the triangles by trigonometry.

In relative Global Navigation Satellite System (GNSS) surveying, a baseline is the line between two GNSS receivers to determine the 3D coordinate difference.