CityData

CityData["name", "property"] gives the value of the specified property for the city with the specified name.

CityData["name"] gives a list of the full specifications of cities whose names are consistent with name.

Examples

Get the population of a city:

CityData["New York", "Population"]
(* 8336817 *)

Get the coordinates:

CityData["Paris", "Coordinates"]
(* GeoPosition[{48.8567, 2.3508}] *)

Please visit the official Wolfram Language Reference for more details.