Cadastre - Cadastral Surveys

Cadastral surveys document the boundaries of land ownership, by the production of documents, diagrams, sketches, plans (plats in USA), charts, and maps. They were originally used to ensure reliable facts for land valuation and taxation. An example from early England is the Domesday Book. Napoleon established a comprehensive cadastral system for France that is regarded as the forerunner of most modern versions.

The Public Lands Survey System is a cadastral survey of the United States originating in legislation from 1785, after international recognition of the United States. The Dominion Land Survey is a similar cadastral survey conducted in Western Canada begun in 1871 after the creation of the Dominion of Canada in 1867. Both cadastral surveys are made relative to principal meridian and baselines. These cadastral surveys divided the surveyed areas into townships, square land areas of approximately 36 square miles (six miles by six miles; some very early surveys in Ohio created 25 square mile townships when the design of the system was being explored). These townships are divided into sections, each approximately one mile square. Unlike in Europe this cadastral survey largely preceded settlement and as a result greatly influenced settlement patterns. Properties are generally rectangular, boundary lines often run on cardinal bearings, and parcel dimensions are often in fractions, or multiples of, chains. Land descriptions in Western North America are principally based on these land surveys.

Cadastral survey information is often a base element in Geographic/Land Information systems used to assess and manage land and built infrastructure. Such systems are also employed on a variety of other tasks, for example, to track long-term changes over time for geological or ecological studies, where land tenure is a significant part of the scenario.