The entrance to this Tehran Metro station may be crowded, but it's nothing compared to the car traffic. The Iranian capital's subway system has four lines.
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Tehran's subway system, like much of the city, is covered in art installations. The metro began operating in 1998 with three stations; there are now 70 stations throughout the city.
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The system transports nearly 2 million people per day, according to the Tehran Urban & Suburban Railway Operation Co.
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The Metro is incredibly clean -- no hardened gum, or even dust, to be seen.
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A man sells olives for hungry commuters outside one station.
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A man and his young son watch the tunnel go by.
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Any prepared urban traveler comes with snacks -- in this case, sunflower seeds.
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Not missing an opportunity, the subway's handles double as ad space.
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The subway system has cell phone coverage both in stations and tunnels.
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A man sells balloons -- or tries to sell balloons -- on a train full of mostly uninterested commuters.
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This is what he is up against -- a public service announcement warning commuters against buying from subway salesmen.
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Driving is "a waste of time and a waste of money," says Nima, center; using the Metro is much easier.
