Map - Calderdale

Calderdale is a metropolitan borough of West Yorkshire, England, whose population in 2020 was 211,439. It takes its name from the River Calder, and dale, a word for valley. The name Calderdale usually refers to the borough through which the upper river flows, while the actual landform is known as the Calder Valley. Several small valleys contain tributaries of the River Calder.

Calderdale covers part of the South Pennines, and the Calder Valley is the southernmost of the Yorkshire Dales, though it is not part of the Yorkshire Dales National Park. The borough was formed in 1974 by the merger of six local government districts, from east to west Brighouse, Elland, Halifax, Sowerby Bridge, Hebden Bridge and Todmorden. Mytholmroyd, together with Hebden Bridge, forms Hebden Royd.

Halifax is the commercial, cultural and administrative centre of the borough. Calderdale is served by Calderdale Council, which is headquartered in Halifax, with some functions based in Todmorden.

The Roman settlement of Cambodunum was probably located within Calderdale. A Roman fort has been excavated in Slack, which is in the neighbouring borough of Kirklees, but its identity is not yet certain.

The borough was formed on 1 April 1974, under the Local Government Act 1972, by the merger of the then county borough of Halifax, the boroughs of Brighouse, Todmorden and the urban districts of Elland, Hebden Royd, Ripponden, Sowerby Bridge, part of Queensbury and Shelf urban district and Hepton Rural District.

The Coat of arms of Calderdale Metropolitan Borough Council was granted to the new council just a few months after the borough was formed. The Paschal lamb is the emblem of John the Baptist, the patron saint of wool workers. It was shown on the former arms of Halifax. The green and blue wavy line of the shield symbolises the River Calder and Calder Valley. The white rose is for Yorkshire. The crest shows a rose bush with nine white flowers representing the nine former authorities that now comprise the Calderdale district. The bush is shown growing out of a mural crown, a common feature in municipal arms. The lion supporters are taken from the arms of Halifax and also for England. A lion also featured on the shield of the arms of Brighouse. The black crescents, also from the arms of Brighouse, are featured on the arms of the Brighouse family. The blue wave around each lion's collar is from the arms of Todmorden and represents the Calder again. The motto, Industria arte prundentia, is Latin for 'Industry, skill, and foresight'. The formal description, or blazon, of the arms is: "For the arms: Vert a Paschal Lamb proper supporting over the shoulder a Cross Staff Or flying therefrom a forked Pennon of St. George between in chief a Bar wavy Argent charged with a Barruret wavy Azure and in base a Rose Argent barbed and seeded proper; and for the crest: On a Wreath Argent and Vert out of a Mural Crown a Rose Tree of nine branches proper each terminating in a Rose Argent barbed and seeded proper; and for the supporters: On either side a Lion Or gorged with a collar wavy Azure and holding aloft in the interior forepaw a Crescent Sable; Motto: INDUSTRIA ARTE PRUDENTIA."