5) Reaching Those Cities

Hats off to Global Gates for the way they keep on adding to the descriptions of primary cities: https://globalgates.info/gateway-cities/#explore.  What exactly is the definition of a ‘Global gateway cities?’  They derive their definition and value from their relationship to ‘reaching the ends of the earth’.  So ‘global gateway cities’ are a means to reaching the ends of the earth, and not an end in themselves.