45,000 Seats Daily: The World’s Number-One Route

Seoul Gimpo to Jeju is the world’s number-one route this year by total seats. With 16.5 million available, it has nearly twice as many as second-placed Hanoi to Ho Chi Minh City. Nine airlines serve Jeju from Gimpo, with nearly 25% of flights by widebodies.

Korean A330-300
Seoul Gimpo-Jeju has six times the volume of seats as the USA’s largest route, JFK to Los Angeles. Photo: Fedor Leukhin via Wikimedia.

The world’s top-10 routes this year

Looking at total seats provided by OAG, the world’s top-10 routes this year are as follows. All are domestic, and all but one is within Asia and the Middle East. With 16.5 million seats, Seoul Gimpo to the South Korean tourist island of Jeju, 280 miles away, is the world’s number-one route by this measure. (And also by total flights.) While an oversimplification, this one route has over 45,000 seats every day.

  1. Seoul Gimpo to Jeju: 16.5 million seats this year
  2. Hanoi-Ho Chi Minh City: 8.7 million
  3. Tokyo Haneda-Sapporo: 8.4 million
  4. Beijing Capital-Shanghai Hongqiao: 8.1 million
  5. Tokyo Haneda-Fukuoka: 7.9 million
  6. Shanghai Hongqiao-Shenzhen: 6.4 million
  7. Shanghai Hongqiao-Guangzhou: 6.4 million
  8. Riyadh-Jeddah 6.2 million
  9. Seoul Gimpo-Busan 5.8 million
  10. Cancun-Mexico City: 5.7 million
World's top routes in 2021
For greater readability, this map includes only routes within the Far East. If 2021 is compared with 2019, the top-10 are down by 56 million seats (!), and Melbourne-Sydney, Mumbai-Delhi, and Hong Kong-Taipei have fallen out of the list for obvious reasons. Image: OAG Mapper

Nine airlines fly Seoul Gimpo to Jeju

Not only is Gimpo-Jeju the world’s densest route, but it is also down by just 5.3% from the 17.4 million seats it had in 2019. Jeju, the so-called Hawaii of South Korea, is incredibly popular because it is straightforward and cheap to reach, has a very short flight, and has some of the best scenery and beaches in the country. The huge amount of air service is also likely because there is no real alternative to reaching the island.

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Nine airlines serve the route this year, with Asiana and Korean Air having nearly half of the market with over eight million seats. If their subsidiaries are included, these two groups have nearly three-quarters of all seats. New entrant Air Premia, whose fleet consists only of Boeing 787-9s, launched operations on this route on August 11th ahead of long-haul service.

  1. Asiana: 25.2% of the market
  2. Korean Air: 23.6%
  3. Jeju Air: 17.2%
  4. Jin Air: 12.6%
  5. T’way Air: 8.8%
  6. Air Busan: 6.5%
  7. Air Seoul: 5.0%
  8. Air Premia: 1.2%
  9. Hi Air: 0.1%
Asiana A321
Asiana is the largest carrier between Gimpo and Jeju. Photo: byeangel via Flickr.

Widebodies are regularly used

Many aircraft are used on this short route, which typically has a flight time of about one hour. While the commonplace B737-800 has a firm grip on the market, multiple widebodies are used, together with the A220-300 with Korean Air and the ATR-72 with Hi Air. Indeed, widebodies have almost one-quarter of all seats, although that’s down from 30% in 2019.

  1. B737-800: 41.9% of the market
  2. A321ceo: 15.1%
  3. B737-900: 13.2%
  4. A330-300: 10.8%
  5. B767-300ER: 9.8%
  6. A321neo: 2.1%
  7. A220-300: 1.9%
  8. B777-200: 1.7%
  9. A320: 1.6%
  10. B787-9: 1.2%
  11. B777-300ER: 0.4%
  12. ATR-72: 0.1%
Jeju Air B737
The B737-800 is the most commonly used aircraft, including with Jeju Air. Photo: Anna Zvereva via Flickr.

Up to 128 flights a day

As hard as it is to comprehend, up to 128 flights will be operated on this route each day before the summer ends. Looking at one random date this month, there are 17 flights to Jeju between 06:00 and 07:00 alone, one every three and a half minutes.

Have you flown from the world’s densest route? Share your experiences in the comments.