Think you know about aviation? These statistics will still surprise you.

1. The world’s busiest air route

What’s the busiest air route in the world? Heathrow to JFK? Hong Kong to Singapore?

Not quite. The most crowded flight path on Earth, according to aviation analyst OAG, is actually the 280-mile hop from Seoul Gimpo (stop sniggering) to Jeju International, the gateway to a Unesco-listed island billed as South Korea’s answer to Hawaii. A staggering 13,460,306 passenger journeys were made between the two airports in 2017; by comparison, less than three million travelled between Heathrow and New York’s JFK.

Second on its list is Melbourne-Sydney, with 9,090,941, while third place goes to Sapporo-Tokyo Haneda, with 8,726,502. In fact, nine of the 10 busiest air routes are domestic services.

The busiest international route is Hong Kong-Taipei, with 6,719,030 passenger journeys in 2017, followed by Jakarta-Singapore Changi, with 4,810,602. Europe’s busiest service, meanwhile, is Izmir-Istanbul Ataturk, while the busiest flight from the UK is Dubai-Heathrow.