Rizzibird From Germany, joined Dec 2000, 232 posts, RR: 2 Reply 6, posted (11 years 11 months 4 weeks 13 hours ago) and read 916 times:
FRA would be my guess. It most certainly has more airlines than LHR as London has several airports and some airlines are not even alowed to fly into LHR (think of American carriers, except for UA and AA). In comparison almost every major flies into FRA. Furthermore FRA has more Eastern European airlines than LHR. So FRA should be number one in Europe, and I would think it is the number one in the world as well.
Mah4546 From Sweden, joined Jan 2001, 31117 posts, RR: 74 Reply 7, posted (11 years 11 months 4 weeks 13 hours ago) and read 904 times:
I'm almost 100% postivie that in the world it is FRA and in the Western Hemisphere it is MIA. A friend who used to work for AA in MIA (and now at DFW) told me, I'm not sure if he was correct. But that list includes charter, cargo, and scheduled. As for scheduled, it is probably JFK in the US. If my memory serves me right, MIA is served by 116 airlines, including 36 US carriers (16 scheduled passenger) and 82 international carriers (41 scheduled passenger).