New data shows airports with the most international connections, and London’s Heathrow Airport kept its top spot. The airport has more than 66,000 possible international connections when considering in-bound and outgoing flights, during a six-hour slot on its busiest day in 2018.

The data comes from air travel intelligence company OAG’s Megahubs International Index 2018, which looks at the number of scheduled connections to and from international flights with the number of destinations served from the world’s 200 largest airports.

The second-highest-ranking airport was Chicago O’Hare (ORD), followed by Frankfurt (FRA), Amsterdam’s Schiphol (AMS) and Toronto Pearson (YYZ).

“Robust demand for international air travel is making Asia-Pacific a pivotal region for connecting flights, and the continued year-round growth of Chinese outbound travel is a decisive factor,” said Mayur Patel, regional sales director, JAPAC, OAG.

“Asia’s dominance is clear to see, but we are likely to see some interesting movements when the new Beijing [Daxing] airport opens. With China driving air travel growth, we expect hub connectivity to Hong Kong, currently undergoing unprecedented growth, driven by mainline operators (Cathay Pacific and Cathay Dragon) will undoubtedly see further evolution.”

The report also showed the world’s busiest airports, with Atlanta (ATL) remaining the busiest, seeing around 104 million passengers in 2017. Second was Beijing Capital International Airport and third was Dubai International Airport.