The Seoul subway, which has been operating for four decades, has traveled far enough to make two round trips to the sun. Seoul Metro, which operates subway lines 1 through 4, began operating the first route back in 1974. Since then, the accumulated operating distance had reached 567.9 million km by July this year, Seoul Metro said Thursday.
That is 3.8 times the distance between the earth and sun (149.6 million km) and 62,947.8 km per day.
The accumulated passenger load since 1974 stood at 36.2 billion people. When subway line No. 1 began running in 1974, some 3,100 people used it each year. The number of passengers began to rise after lines 2, 3 and 4 were completed in 1984, and 19 years later the number of users surpassed 10 billion in 1993.
Since then, the subway added 10 billion more passengers every seven years, reaching 20 billion in 2000 and 30 billion in 2007. As of 2010, 1.48 billion passengers used lines 1 through 4 each year, which boils down to 4.04 million users a day.
The number of people using the Paris Métro, which started operating in 1900, stood at 1.15 billion in 2010, while the London Underground, which began running in 1863, has 868 million people using it every year. The New York Subway has 490 stations, four times more than the Seoul metro system, but has only 1.13 billion users per year.