A principal meridian is a

meridian Meridian or a meridian line (from Latin ''meridies'' via Old French ''meridiane'', meaning “midday”) may refer to Science * Meridian (astronomy), imaginary circle in a plane perpendicular to the planes of the celestial equator and horizon * ...

used for survey control in a large region.

Canada

The Dominion Land Survey of

Western Canada Western Canada, also referred to as the Western provinces, Canadian West or the Western provinces of Canada, and commonly known within Canada as the West, is a Canadian region that includes the four western provinces just north of the Canada� ...

took its origin at the First (or Principal) Meridian, located at 97°27′28.41″ west of

Greenwich Greenwich ( , ,) is a town in south-east London, England, within the ceremonial county of Greater London. It is situated east-southeast of Charing Cross. Greenwich is notable for its maritime history and for giving its name to the Greenwic ...

, just west of

Winnipeg, Manitoba Winnipeg () is the capital and largest city of the province of Manitoba in Canada. It is centred on the confluence of the Red and Assiniboine rivers, near the longitudinal centre of North America. , Winnipeg had a city population of 749 ...

. This line is exactly ten miles west of the Red River at the Canada–United States border. Six other meridians were designated at four-degree intervals westward, with the seventh located in British Columbia; the second and fourth meridians form the general eastern border and the western border of

Saskatchewan Saskatchewan ( ; ) is a province in western Canada, bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on the south by the U.S. states of Montana and North ...

United States

In the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

Public Land Survey System, a principal meridian is the principal north-south line used for survey control in a large region, and which divides townships between east and west. The meridian meets its corresponding baseline at the point of origin, or initial point, for the land survey. For example, the Mount Diablo Meridian, used for surveys in California and Nevada, runs north-south through the summit of Mount Diablo. Often, meridians are marked with roads, such as the Meridian Avenue in

San Jose, California San Jose, officially San José (; ; ), is a major city in the U.S. state of California that is the cultural, financial, and political center of Silicon Valley and largest city in Northern California by both population and area. With a 2020 popul ...

, Meridian Road in Vacaville, California, both on the Mount Diablo Meridian, Meridian Road in

Wichita, Kansas Wichita ( ) is the largest city in the U.S. state of Kansas and the county seat of Sedgwick County. As of the 2020 census, the population of the city was 397,532. The Wichita metro area had a population of 647,610 in 2020. It is located in ...

on the Sixth Principal Meridian, and Meridian Avenue in several western Washington counties generally following the Willamette Meridian. Baseline Road or Base Line Street extends for about from

Highland, California Highland (and neighboring "East Highlands") is a city in San Bernardino County, California, United States. The population of the city was 53,104 as of the 2010 census, up from 44,605 at the 2000 census. The term ''Highland'' also refers to a ge ...

east of San Bernardino to

La Verne, California La Verne is a city in Los Angeles County, California, United States. The population was 31,063 at the 2010 census, down from 31,638 at the 2000 census. History The European history of the area dates back to the 1830s when Ygnacio Palomare ...

where it meets Foothill Boulevard.

External links

The Principal Meridian Project (US)History of the Rectangular Survey System
Note: this is a large file, approximately 46MB. Searchable PDF prepared by the author, C. A. White.

Surveying Meridians (geography) {{Geo-term-stub

Canada

United States

See also

External links