Main Page | See live article | Alphabetical index


Surveying is the technique and profession of determining the boundaries of land.

First, benchmarks are located at known latitude and longitude. They are far enough apart from each other that spherical geometry is not accurate enough to compute their distances, and a geoid must be used. The ancestor of all benchmarks is the Greenwich meridian.

Then, when a plat (US) or plan (UK) is drawn, the distance of a control point from a benchmark is given, as well as the location whose north is being used. If the area is less than 400 km2, the earth can be treated as flat, but the Cartesian coordinates used in surveying do not match the meridians and parallels except at one meridian.

The standard instrument for surveying is the theodolite.

Modern surveying also makes use of laser theodolites and satellite positioning systems.

Types of survey include:

Famous surveyors include: