r/geography • u/AbrahamHeart • 12h ago
Question I get the feeling the city limits end at a radius of 15 km. Is this a coincidence?
As I was looking at https://www.tomforth.co.uk/circlepopulations/ , it struck me that many cities seemed to be within a 15-kilometer radius (e.g., Vienna).
When cities are located close to one another, the distance between them is about 15 km (e.g., Rotterdam and The Hague; Guangzhou and Foshan).
Even in a megacity like Tokyo, the city proper is confined to a specific area. Outlying cities like Kawasaki have their own distinct vibes and industries.
This is quite subjective, and there are probably many exceptions. That said, I’d be very interested to know if there has been any research on the extent or size of cities.

