Traditionally, cities are defined as large human settlements, with no one standardized definition applied internationally. Frequently, national governments have criteria they use to define urban areas. These criteria can vary to include aspects such as administrative boundaries, living conditions or population density. Another approach is what is termed “urban agglomeration”, which considers the extent of an urban area, or sometimes, that of a built-up area, to identify a city’s boundaries.

Please note that the English document is currently the most up to date version of the technical guideline. The French and Spanish translations are being reviewed and will be soon available for download.