What is the largest city in the world?

A city can be defined by its administrative boundaries, otherwise known as city proper. UNICEF defines city proper as, "the population living within the administrative boundaries of a city or controlled directly from the city by a single authority." A city proper is a locality defined according to legal or political boundaries and an administratively recognised urban status that is usually characterised by some form of local government.[1][2][3] Cities proper and their boundaries and population data may not include suburbs.[4]

The use of city proper as defined by administrative boundaries may not include suburban areas where an important proportion of the population working or studying in the city lives.[4] Because of this definition, the city proper population figure may differ greatly with the urban area population figure, as many cities are amalgamations of smaller municipalities (Australia), and conversely, many Chinese cities govern territories that extend well beyond the traditional "city proper" into suburban and rural areas.[5] The Chinese municipality of Chongqing, which claims the largest city proper in the world by population, comprises a huge administrative area of 82,403 km2, around the size of Austria. However, more than 70% of its 30-million population are actually agricultural workers living in a rural setting.[6][7]

ChoingQing, China is the largest city proper in the world by population. It has a huge administrative area of 82403 km2. While, it governs territories that covers both suburban and rural areas, which extend well beyond the traditional city proper.