The 10 busiest international air routes in the world in 2019 before coronavirus crippled demand for plane travel

Planes parked at London's Gatwick Airport in 2010.Aviation-images.com/Universal Images Group/Getty Images

• Travel data firm OAG released its annual Busiest Routes report listing the top 10 busiest international routes in terms of the number of seats sold.
• Nine out of the 10 routes on the list were fully within the Asia-Pacific region and only one route touching North America and Europe.
• Eight routes touched Hong Kong and Singapore with the flag carriers of the two economic hubs, Singapore Airlines and Cathay Pacific, being featured on most of the sectors.
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Airlines were flying more than ever in 2019 as the world grew in interconnectivity.

As part of its annual Busiest Routes report, travel data firm OAG determined the busiest international routes in terms of the number of seats sold for 2019.

All but one route on the top 10 list for busiest international routes were entirely within the Asia-Pacific region. The cities of Singapore and Hong Kong were among the top featured on the list, with eight out of 10 routes touching either of the economic hubs.

The busiest routes were typically less than 1,000 nautical miles in duration, with only one long-haul route featured on the list. Some routes saw as many as 10 airlines operating between the two cities with a minimum of four airlines on the least dense route based on the number of airlines served.

With the novel coronavirus posing a continued threat to aviation, it may be years before these routes achieve the same numbers again.

Take a look at which international routes had the most seats for sale during 2019.