Which is the busiest flight route in the world?

No, its not what you thought of, neither Melbourne-Sydney or Delhi-Mumbai but it is Seoul (Capital of South Korea) to Jeju a tropical island, off the southern coast in the Korean Peninsula. There are at least 180 flights per day from Jeju to Seoul, flight time ranging from 45 minutes to 1 hour. Jeju Island is famous for its beaches,resorts,volcanoes and hiking trips. According to The Independent atleast 13.4 million flew this route. Airlines operate a diverse fleet of aircraft, including widebodies. This route has beaten the Singapore-Kuala Lumpur and Sydney-Melbourne. The cost of this route is roughly $67 making it affordable for people from all economic backgrounds.

Here is a link to a video of simply aviation who flew this route 4 times in 1 day!

https://www.youtube.com/watch?v=a0T-yL8KSu4

Photo credit- KN Aviation