control survey

A control survey is a foundational type of land measurement used to establish precise reference points, lines, and elevations across a large area. These reference points serve as benchmarks for more detailed surveys and construction projects, ensuring consistency and accuracy. For example, surveyors set up fixed markers on the ground that define the geographic position and elevation, which are then used to map out roads, buildings, or other infrastructure. Think of control surveys as creating a reliable coordinate system or "frame of reference" that guides all subsequent surveying and development work in the area.