Many large cities are found at locations with certain first-nature advantages. However, those exogenous locational features may not be the most dominant forces dictating the spatial pattern of cities.
There are many other factors into account why cities are where they are.
The 10-mile rule and spheres of influence
If you measure the distance separating two neighboring pre-industrial towns, you will likely find 10 miles (16 km). Before the appearance of cars, people in country settlements could walk without considerable effort only 5 miles (~8 km) to the nearest settlement in a single day for work and stores. Consequently, towns formed a five-mile sphere of influence, forming a typical 10-mile span between medium-sized settlements.
Some of these small towns develop into large cities with more people that can support more specialized shops and services, with spheres of influence extending hundreds of miles.
Oceans
Fourteen of the global’s largest 15 cities are located near the sea or ocean. Oceans have constantly been the most workable, cost-effective, existing way of transporting goods over remote distances. Hence, for a city to remain economically dynamic, it must locate itself close to an ocean or significant river.
Resources
Natural resources provide cities to benefit as manufacturing, business, and transport centers. Modern technology enables profitable resources such as oil and gas to be moved over long distances. As a result, we have observed the growth of cities such as Dubai, which profit from managing resources, notwithstanding not being geographically located near them.
Mountains
For settlements, highlands can be both a help and a barrier. They not only play a role as a barrier to transportation and trade, but they also form a natural protection from attack. Moreover, mountains have abundant minerals and natural resources. Therefore, many mountain-located ancient cities flourished.
Continents and Climate
There are just 32 of the 220 largest cities located in the Southern Hemisphere, not only because of the land area in the southern hemisphere, less than in the northern hemisphere. According to the book “Guns, Germs, and Steel: The Fate of Human Societies” by Jared Diamond, as a result of east-west span continents of the Northern Hemisphere, rather than a long north-south span, the climate across large extents of land remain almost the same, which provided ancient empires such as the Mongols to conquer large expanses of land with the same animals and tools. As a result, an asymmetrical number of major cities are located in the Northern Hemisphere.
Reddit user BerryBlue_BlueBerry created an exciting world map of countries ranked by the distance between the two most populated cities. Many of these significant cities in every country owe their appearance and development to the aforementioned facts.
If using other definitions results in different sets of most populated cities in a country, the meaning closest to ”Metropolitan Area” is the prior choice in the ranking. While other definitions like ”City Proper”, ”Conurbation”, or involving ”Disputed Areas” are also included here but labeled with brackets, solid dots, and dotted lines.
The United States has the most significant distance between the two most populous cities among all countries. Megapolises New York City and Los Angeles are located on the shores of the Atlantic and Pacific Oceans, which contributed to their appearance and rapid growth.
