I thought Berlin would be in the list because according to Citypopulation it's the second biggest urban area of Germany, with 4.35 million inhabitants.
If you ask me Hamburg should be on the list. It has the second largest urban area when looking at a single big city + its urban area and not a few major ones in a combined urban area like Duisburg/Essen/Bochum/Dortmund (Ruhr) or Cologne/Düsseldorf. No German will ever say that Berlin is not the biggest city. Then again I'm sure some of the other cities urban Areas include other major cities but don't get to be mentioned.
Alright, no loosely-defined regions in Germany. Fine. But even then the very definite Hamburg metropole (5.3 mio) as a second place after Berlin (6.1 mio) should make the cut.
Even though both have seen their populations increased, Monterrey has concentrated more of the new economic opportunities of its region (like Tesla), while the Bajío region (where Guadalajara is) has had its opportunities spreaded across the region, making the population spread too.
By City Proper, Brisbane is the biggest (five times bigger than Sydney even), hence why it's not really used in Australia. Sydney has a slightly larger "urban centre" population, whereas Melbourne has recently overtaken Sydney in "significant urban area" by sprawling out to encompass other cities (mainly Melton).
You'd think that at some point I'd learn how to spell Medellin and not waste 30 seconds trying to get it correct. But then again I waste 20 seconds every time I have to go back a remove the second "L" in Brasilia.
Please also allow the spelling Jidda(h).
Oh well...I guess I'll try again.
Berlin: 4.85
Frankfurt: 3.30
Hamburg: 2.93