Property line describes the legal boundary of a parcel of land. The boundary is established by a professional surveyor

Surveying

See Also: Public Land Survey SystemSurveying or land surveying is the technique, profession, and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them...

 using a transit

Theodolite

A theodolite is a precision instrument for measuring angles in the horizontal and vertical planes. Theodolites are mainly used for surveying applications, and have been adapted for specialized purposes in fields like metrology and rocket launch technology...

 and or modern Global Positioning System (GPS)

Global Positioning System

The Global Positioning System is a space-based global navigation satellite system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites...

 technology. The coordinates of the property line are often described on a drawing called a "plot plan" or "plat

Plat

A plat in the U.S. is a map, drawn to scale, showing the divisions of a piece of land. Other English-speaking countries generally call such documents a cadastral map or plan....

" by indicating the length of the boundary along a specific compass bearing in relation to a verifiable "point of beginning". The metes and bounds

Metes and bounds

Metes and bounds is a system or method of describing land, real property or real estate. The system has been used in England for many centuries, and is still used there in the definition of general boundaries...

method is also used to provide a legal description of a property.