World's busiest airline route by passenger numbers: Melbourne-Sydney second busiest

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

The correct answer will surprise you. The most crowded flight path on Earth, according to aviation analyst OAG, is actually the 450-kilometre hop from Seoul Gimpo (stop sniggering) to Jeju International. 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.

Melbourne-Sydney also comes in at number based on the number of flights on the route, with 54,519 flights a year, according to OAG.

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.

According to new data from the International Air Transport Association (IATA), airlines carried 4.1 billion passengers in 2017, an increase of 7.3 per cent over 2016, representing an additional 280 million trips by air.

Busiest air routes in the world

Passengers in 2017

  1. Jeju - Seoul Gimpo (CJU-GMP) 13,460,306
  2. Melbourne - Sydney Kingsford Smith (MEL-SYD) 9,090,941
  3. Sapporo - Tokyo Haneda (CTS-HND) 8,726,502
  4. Fukuoka - Tokyo Haneda (FUK-HND) 7,864,000
  5. Mumbai - Delhi (BOM-DEL) 7,129,943
  6. Beijing Capital - Shanghai Hongqiao (PEK-SHA) 6,833,684
  7. Hanoi - Ho Chi Minh City (HAN-SGN) 6,769,823
  8. Hong Kong - Taiwan Taoyuan (HKG-TPE) 6,719,030
  9. Jakarta - Juanda Surabaya (CGK-SUB) 5,271,304
  10. Tokyo Haneda - Okinawa (HND-OKA) 5,269,481

Busiest international air routes

Passengers in 2017

  1. Hong Kong - Taiwan Taoyuan (HKG-TPE) 6,719,030
  2. Jakarta - Singapore Changi (CGK-SIN) 4,810,602
  3. Hong Kong - Shanghai Pudong (HKG-PVG) 4,162,347
  4. Kuala Lumpur - Singapore Changi (KUL-SIN) 4,108,824
  5. Bangkok Suvarnabhumi - Hong Kong (BKK-HKG) 3,438,628
  6. Dubai - London Heathrow (DXB-LHR) 3,210,121
  7. Hong Kong - Seoul Incheon (HKG-ICN) 3,198,132
  8. Hong Kong - Singapore Changi (HKG-SIN) 3,147,384
  9. New York JFK - London Heathrow (JFK-LHR) 2,972,817
  10. Hong Kong - Beijing Capital (HKG-PEK) 2,962,707

Why are so many people flying to Jeju?

More than 26 million passengers use Jeju International each year.

So what the devil is Jeju, and why are so many rushing to see it?

It's actually the capital of an island, Jejudo, which might just be the most popular holiday destination you've never heard of.

Unesco-listed, and billed as South Korea's answer to Hawaii, it's pure Instagram gold, and home to dramatic volcanic landscapes, underground caves, hiking trails and scenic beaches.

Halla Mountain, at 1940m above sea level, is South Korea's highest peak, while the cone of Seongsan Ilchulbong, or "Sunrise Peak", is particularly spectacular.

In 2011 Jejudo was named among the "New7Wonders of Nature", though there were accusations that its selection was down not just to its beauty, but also the readiness of tourism and marketing organisations to stump up cash – including taxpayers' money – to support its campaign.

There are also casinos, which help lure travellers from China, and, thanks to the island's self-governing status, anyone can visit without a visa.

Bizarrely, there's also a sex-themed park, Jeju Love Land, which features phallus statues, interactive exhibits on the "masterbation cycle", and other sculptures of humans in flagrante. Love Land is said to owe its existence to Jejudo's popularity as a honeymoon destination. Young newlyweds would arrive knowing next to nothing about the birds and the bees so some hotel employees offered to share their expertise. The island soon became an unofficial centre for sex education, making the theme park entirely logical.

But Jejudo also has a dark side. In 1948 and 1949, the South Korean government brutally put down an attempted uprising on the island. Villagers, including women and children, were massacred, and as recently as 2008 mass graves were still being uncovered. Some 30,000 people died as a result of the uprising, with a further 40,000 fleeing to Japan, and the atrocities are remembered at the 4.3 Peace Park memorial.

The world's busiest airlines

The top five airlines ranked by total scheduled passenger kilometers flown, were:

1. American Airlines (324 billion)

2. Delta Air Lines (316.3 billion)

3. United Airlines (311 billion)

4. Emirates Airline (289 billion)

5. Southwest Airlines (207.7 billion)

Star Alliance maintained its position as the largest airline alliance in 2017 with 22 per cent of total scheduled traffic (in RPKs), followed by SkyTeam (19 per cent) and oneworld, which Qantas is a member of (16 per cent).

See also: World's best airline for 2018 named as Virgin's ranking plummets

Which is the world's busiest airport?

It's not quite as surprising as Jeju, but not far off. Nope, it's not Heathrow, Beijing or even Dubai. The busiest on the planet is actually Hartsfield-Jackson Atlanta International – as it has been since 1998 (20 years in a row). Almost 104 million passengers passing through its terminals in 2017 – that's slightly more than the population of the Philippines.

The biggest airline at Atlanta, by some margin, is Delta. It operates 73 per cent of flights. And a remarkable 219 cities have non-stop services to it.

See also: The world's best airport named for 2018 named

The world's busiest airports

Hartsfield-Jackson has remained the world's busiest passenger airport since 1998

Passengers in 2017

  1. Hartsfield–Jackson Atlanta International Airport 104m
  2. Beijing Capital International Airport 95m
  3. Dubai International Airport 88m
  4. Tokyo Haneda Airport 85m
  5. Los Angeles International Airport 84m
  6. Chicago O'Hare International Airport 79m
  7. London Heathrow Airport 78m
  8. Hong Kong International Airport 72m
  9. Shanghai Pudong International Airport 70m
  10. Paris-Charles de Gaulle Airport 69m

The Telegraph, London with Traveller

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