The United Counties of Northumberland and Durham was a
historic county in the
Canadian province
Within the geographical areas of Canada, the ten provinces and three territories are sub-national administrative divisions under the jurisdiction of the Canadian Constitution. In the 1867 Canadian Confederation, three provinces of British North ...
of
Ontario
Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...
. The two counties were originally combined in the
District of Newcastle formed in 1802, and continued as united counties from 1850 until January 1, 1974 when portions of
Durham County were amalgamated with adjacent
Ontario County to form the
Regional Municipality of Durham
The Regional Municipality of Durham (), informally referred to as Durham Region, is a regional municipality in Southern Ontario, Canada. Located east of Toronto and the Regional Municipality of York, Durham forms the east-end of the Greater To ...
.
Manvers Township went to
Victoria County Victoria County is the name of several locations:
In Australia:
*Victoria County, Western Australia
* County of Victoria, South Australia
In Canada:
* Victoria County, New Brunswick
* Municipality of the County of Victoria and the eponymous histo ...
and what is now
Cavan-Monaghan went to
Peterborough County
Peterborough County is located in Southern Ontario, Canada. The county seat is Peterborough, which is independent of the county.
The southern section of the county is mix of agriculture, urban and lakefront properties. The northern section of th ...
. What is now
Port Hope remained in the area which was continued as
Northumberland County, while Durham County was dissolved.
Former counties in Ontario
Populated places disestablished in 1974
{{Ontario-geo-stub