Most people have seen — or taken a ride on — a train at one time or another. But did you realize that there are trains that run underground or on tracks way up in the air?

It’s true! They’re called “subways” when they’re belowground and “elevated trains” — “els” — when they’re up in the air.

These systems are called “mass transit” or “mass transportation” systems because they transport large numbers of people around urban (city) areas. In addition to the convenience of getting to and from areas quickly, mass transportation systems help to reduce the amount of air pollution from automobiles and reduce traffic congestion.

Mass transportation systems began to develop in the late 19th century. In the early to mid 1800s, the population of cities around the world began to increase dramatically. In New York City, for example, the population increased almost 60 percent each decade during this time.

As cities became more crowded, traffic congestion became a huge problem. People in New York City were once known to claim that you could drive halfway to Philadelphia quicker than you could drive the length of Broadway (one street within the city).

As city leaders began to search for transportation alternatives that would relieve congestion, subways and elevated train lines were born. The first subway system — the London Underground — opened in 1863.

America’s first subway system opened in Boston on September 1, 1897. New York City’s system opened a few years later in 1904.

The earliest systems used steam locomotives, but a switch to electric trains was made as soon as technology allowed.

Other cities around the United States, such as Philadelphia and Chicago, also developed their own subway and elevated train systems. Although mass transportation suffered a decline after World War II, as more and more Americans turned to automobiles, subway use began to increase again in the 1970s.

San Francisco’s Bay Area Rapid Transit (BART) system became a model for other cities to follow. Baltimore, Miami, Atlanta, Washington D.C. and Los Angeles developed systems. People once again began to use these systems for their convenience and cost savings.

Around the world, more than 160 cities have mass transportation systems. And more than two dozen cities currently have new systems under construction.

Although the cost to build these systems is high, they usually pay off in the long run. Mass transportation systems — over time — transport more people using less land and fewer environmental resources… all at a lower cost than similar road transportation systems.

Today, the largest mass transportation system in the world, based on length of routes and number of stations, is the New York City subway system. By length of lines, though, the largest systems are the London Underground and the Shanghai Metro. The most-used systems are the Tokyo Metro, Moscow Metro and Seoul Metro.


16 Join the Discussion

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    • Have any of you ever been a passenger on a subway, Kerrick Elementary EBD/2nd Grades Classrooms? We enjoy riding them when we visit other places! It’s fun to travel under the ground and arrive at a new place so quickly! Thank you for your comment today! :-)

  1. We were surprised that the first subway was over 100 years ago. We do not have subways in our community. Thank you for sharing other ways of transportation with us.

    • Hello there, The Beach (Mrs. Guerin’s 2nd Grade Class)! We’re so glad to hear that you learned something new from today’s Wonder! Thank you for leaving us such a great comment! :-)

  2. I loved your time lapse! I think it is really neat how you can see all of that in one minute and twenty three seconds. I also enjoyed watching all of those people scurrying around. I learned a lot and I had no idea that the first subway ride was on September 1, 1897. I think that the next wonder of the day will be something about a storm,tornado, twister or a hurricane.

    • Hi there, Olivia! Thank you for leaving us this awesome comment! We’re glad you liked the video for this Wonder and that you learned so many new things! :-)

  3. Hooray Mrs. Guerin’s class is right below our classroom. So exciting that Wonderopolis is spreading at BES. I think I might go downstairs tomorrow and enjoy the beach after all it is Friday!

    • We’re so happy to have another AMAZING classroom from BES leaving us comments and letting us know all the great things they are learning from their visits to Wonderopolis! :-)

  4. Hey Wonderopolis! I am sooooo glad my teacher showed me this AWESOME website! By the way, bigbigbig thanks for the super WONDER! This is my lucky wonder–going on vacation and using a train!

    • We’re glad your teacher introduced you to Wonderopolis, too, Some Person! We have appreciated your great comments! Have fun on your vacation! :-)

  5. Hey Wonderopolis, I loved the video. I wonder if my mom was on the video because she takes the subway to work. I have been on a subway when we went to see a Broadway show.

    Maddy M.

    • Lots, lots, lots of people take the subway to work each day, Maddy M! It is a very effective way to get around in large cities. We think it’s super neat that you got to ride on a subway when you went to see a Broadway show. What show did you see? :-)

    • What a GREAT comment, Ryan! We think our Wonder Friends are pretty AMAZING, and we’re glad to hear that you like Wonderopolis! Thanks so much for visiting us! :-)

    • Hi there, Kat! Thanks for commenting today– we hope you will read the entire Wonder about trains! There is so much to learn and Wonder, we hope you’ll check out the rest of the Wonder! :)

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Have you ever wondered…

  • Do all trains run aboveground?
  • Where was the first subway?
  • What is the largest subway system in the world?

Wonder Gallery

NY subway_shutterstock_23197885Vimeo Video

Try It Out

Do you have any mass transportation areas where you live? Depending on the size of the town you live in, you may or may not have such options.

If you live in a large city, research the mass transportation options available in your area. Is there a subway? What about bus lines? Trolley cars? What options exist and what routes do they run?

Where are the nearest stops to your house? Think about the places you travel to on a regular basis. Do you ever use mass transportation for these trips? Why or why not?

Try to figure out how you would get to some of your favorite places by mass transportation. How much would it cost? How long would it take?

If you live in a small city, choose a nearby city that you know has public transportation. Or, if you prefer, you could pretend that you live in a major city, like New York or Tokyo.

Answer the same questions listed above, except use places you’d like to go if you lived in those cities.

Talk with your family about how you normally travel together. Are there times when you could take mass transportation? Would it save you time or money? What positive impacts might there be on the environment if your family used mass transportation more often?

When you’re finished, take a virtual tour of the Beijing subway system. What do you think it would be like to use mass transportation in a foreign city? Other than the obvious issues with reading signs, what other challenges do you think you might face?


Still Wondering

Use National Geographic Xpeditions’ Paris Scope online interactive tool to learn more about the history of Paris by visiting locations via the virtual Paris Metro!


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