I put it next to a city and connect it with a good tram line . Just like you would for a train station or a pier . Watched some utubers put airports in the middle of nowhere with a dedicated railbus lines to and from a city and they always failed with airplanes . It might work but that puts another leg in the ai travel . So I prefer a faster connection to airports ai has access to . Ai using planes also uses trains for fast preference . So if you put 2 airports too close that can be reached by rail , your plane traffic is gonna die . This city main city center was by the passenger station . When I put the airport down , the entire commercial zone spawned up along with the residential off to the right . So I just have 2 of em on my 11 medium map connected by trams to a passenger station in both cities that have a daisy chain line to 3 , 4 other cities 123 with airport 4321 for one side and have 12 with airport 321 for the other