West Yorkshire Built-up Area
The West Yorkshire Built-up Area, previously known as the West Yorkshire Urban Area, is a term used by the Office for National Statistics (ONS) to refer to a conurbation in West Yorkshire, England, based on the cities of Leeds, Bradford and Wakefield, and the large towns of Huddersfield and Halifax. It is the fourth largest urban area in the United Kingdom.
Source: Wikipedia — West Yorkshire Built-up Area (CC BY-SA 4.0)