1. If all of the tracks that make up the NYC subway were laid end to end, they would stretch from New York to Chicago.
2. The green or red globes at many subway entrances actually mean something. As a general rule, entrances with red globes are closed at night, while those with green globes are open 24-7.
3. Only 60% of the subway system is underground.
4. All of the top 10 busiest subway stations are in Manhattan. Times Square takes the No. 1 spot with more than 63 million riders per year.
5. Though the New York City subway is by far the busiest subway system in the United States with 1.7 billion riders annually, it's only the seventh-busiest system in the world. Tokyo, the world's busiest system, sees nearly twice as many riders a year.
6. According to the 14th annual "subway shmutz" survey, passengers named the D train the dirtiest line, while the L was the cleanest.
7. The deepest subway stop is the 191st Street station where the 1 train stops. The platform is 180 feet below street level.
8. The Smith-Ninth streets station is the highest at 88 feet above street level.
9. There is a black-and-white striped board in the middle of every subway station. The conductor needs to point at it to assure that the train has stopped in the right place.
10. There is a tongue-in-cheek, but fairly accurate, economic principle known as the New York Pizza Connection, which states that the average price of a slice of pizza matches the cost of a ride on the subway. When one increases, the other tends to follow.
11. Putting your feet on the seat isn't just rude — it's a crime that cops can arrest you for.
12. When New York's first subway system opened in 1904, Mayor George B. McClean was supposed to ceremonially start the train, then turn over control to a professional motorman. However, the mayor declared that he was "running this train," and ended up driving for most of the journey.
13. A worker excavating under the East River in 1916 survived being sucked through the river and shot up into the air after the pressurized tunnel he was digging cracked.
14. The first female subway conductor was hired in 1917.
15. The worst subway accident in New York's history occurred in 1918 when a conductor who was filling in for a striking motorman lost control of his train while entering a tunnel on Brooklyn's Malbone Street. The crash killed 97 people and injured more than 200 others.
16. The subway started taking tokens instead of coins in 1953 when the fare was raised to 15 cents, as the turnstiles couldn't accept two different types of coins.
17. In the days of tokens, criminals would often intentionally jam turnstiles and then use their mouths to suck tokens out of the slots.
18. In response to this disgusting form of theft, token booth clerks would often sprinkle chili powder or mace into the slots to deter thieves.
19. Despite the prevalence of MetroCards, it was still possible to use tokens until spring 2003, when they were officially deemed obsolete and invalid after 50 years of use.
20. MetroCard swipes are tracked and have successfully been used as an acceptable alibi to acquit people accused of committing crimes.
21. The first air-conditioned subway cars weren't introduced until June 1967, meaning summer in New York used to be even worse.
22. The 7 train was the last train to get AC. By 1993, 99% of the cars were cool.
23. In an attempt to combat rampant graffiti on the subways, officials painted 7,000 subway cars pure white so as to dissuade potential vandals. However, graffiti artists merely viewed "the great white fleet" as a much-needed fresh canvas, and the plan failed horribly.
24. In 1993, 16-year-old Keron Thomas posed as a train conductor and drove an A train for three hours and safely delivered passengers to their destinations before he accidentally triggered an emergency brake on a fast curve.
25. In 2008, 44 old subway cars were dumped into the ocean off of the coast Maryland to serve as an artificial reef.
26. Michael Jackson filmed the music video for "Bad" at the Hoyt-Schermerhorn subway station. The MTA has rejected several proposals to install a memorial to the King of Pop at the station.
27. Due to the popularity of the book and movie The Taking of Pelham 123, train dispatchers generally avoid giving trains leaving Pelham Bay Park a 1:23 departure time.
28. The MTA maintains a fake building in Brooklyn Heights. The brownstone exterior actually contains electrical equipment and a secret entrance to the subway system.
29. There is a secret train platform underneath the Waldorf-Astoria building that extremely rich people could use. President Franklin Roosevelt used the station to help hide the fact that he used a wheelchair.
30. The MTA will email or fax you a "late letter" if a train delay causes you to be late for work.
31. The A train travels the longest route. It's 31 miles from 207th Street in Manhattan to Far Rockaway in Queens.
32. The A train also has the longest gap between stations, as it's a 3.5-mile trip from the Howard Beach/JFK Airport stop to the Broad Channel station.
33. The New York City subway cars traveled a combined 344.9 million miles in 2013.