10 things to know about the Chicago L

The L looks simple on a map: eight colours, a downtown loop, done. Ride it for a few months and you start noticing the seams: a curve that slows every train to a crawl, a station that opened in 2017 to replace two stations that stood a block apart, a colour scheme younger than most of the people who ride under it. Here are ten things about the network that hold up once you check them.

If you want to test what you actually know station by station, the Chicago edition of DailyMetro runs one mystery station a day, and the line-by-line explorer has the full station list if you want to study first.

1. It opened for the World's Fair

Service began on June 6, 1892, on the South Side, ahead of the 1893 World's Columbian Exposition, which is why some of the oldest stations still running today, including 35th-Bronzeville-IIT and Indiana on the Green line, date to that same year. Chicago's rapid transit is one of the oldest in the country, older than the New York City Subway by more than a decade.

2. The Loop is a literal loop, and it is younger than the lines it joins

The name is not a metaphor. Four separate elevated companies (South Side, Lake Street, Metropolitan, and Northwestern) built their own lines into downtown Chicago on their own schedules, and it was the construction of a closed loop of elevated track around the central business district, finished in 1897, that physically stitched them together and gave the neighborhood its name.

3. Despite the name, parts of it have never been elevated

"The L" stands for elevated, but two long stretches run in subway tunnels: the State Street Subway, opened in 1943 under the Red line, and the Dearborn-Milwaukee Subway, opened in 1951 and now carrying the Blue line. Both were built to pull downtown congestion off the original elevated Loop structure, not to change the system's nickname.

4. The colours are newer than you'd think

For most of the twentieth century, riders navigated by route names tied to neighborhoods and branches, not colours. The CTA only assigned the current colour scheme, Red, Blue, Brown, Green, Orange, Pink, Purple, Yellow, in 1993. The Pink line is even younger as a named service: it did not exist as a separate colour until 2006, when a Blue line branch was split off and repainted.

5. Some curves force trains down to walking speed

The L can run up to 55 mph on straight, modern stretches, but its minimum curve radius is about 90 feet, a constraint left over from squeezing elevated track above nineteenth-century city streets rather than through open right-of-way. That is why certain Loop curves, and a few turns elsewhere on the network, make every train slow to a near-stop regardless of how new the cars are.

6. The CTA itself is a 1947 merger

The Chicago Transit Authority did not build the L. It was created in 1947 to take over and unify a set of competing private elevated railroad companies and the city's separate streetcar system, which is part of why the network still reads like several older systems bolted together rather than one designed from scratch.

7. The newest station replaced two that stood almost on top of each other

Washington/Wabash, on the Loop, opened on August 31, 2017, as the system's newest station. It replaced Madison/Wabash and Randolph/Wabash, two stops that had both opened back in November 1896 and sat close enough together that consolidating them into one accessible station had been discussed by planners since at least 1981.

8. One line ran for 48 years without a single station in between

Today's Yellow line has three stops. From 1964, when the shuttle known as the Skokie Swift relaunched nonstop service between Howard and Dempster, until April 2012, it had exactly two, with nothing whatsoever in between. Oakton-Skokie, opened in 2012, was the first new CTA station built since 2001 and the first stop the line had gained in almost half a century.

9. Ridership is measured in the hundreds of millions

According to CTA figures reported on Wikipedia, the L carried about 135.2 million rides in 2025, with weekday ridership averaging roughly 385,500 in early 2026. In DailyMetro's own station-level numbers, drawn from the same reporting, O'Hare is the single busiest stop in the dataset, which tracks with it being both an airport terminus and a transfer point for the whole Blue line.

10. There is an entire downtown station that never opened

Below the Block 37 development on State Street sits a full station shell built to connect the Red and Blue lines, construction on which began in 2005 and was abandoned after costs ran past the initial $213 million budget. It has never carried a single passenger. There is a lot more to say about it, and about the L's other closed and abandoned stops, in the ghost stations piece.