CHICAGO (CBS) — If your commute includes a ride on the ‘L,’ you might end up in the middle of a big party on Tuesday. The CTA is celebrating 125 years of elevated trains in Chicago.

On June 6, 1892, the first elevated trains began running on what is now the Green Line. Back then, it was known as the “Alley L” or the “South L.”

When the trains first began operating, they were made up of wooden passenger cars pulled by small coal-burning steam locomotives.

green line 39th Chicagos Elevated Train System Turning 125

An early ‘L’ train at 39th Street on the South Side ‘L’ in 1893. (Source: Flickr/CTA)

The original ‘L’ ran on tracks from Congress Parkway to 39th Street, just east of State Street; but historian Graham Garfield said 39th Street was its southern terminal for only two months.

“Even before it began running trains, it was planning extensions,” he said.

The destination was 63rd Street and Jackson Park, a destination that became more urgent because of the impending opening of the World’s Columbian Exposition on May 1, 1893.

green line 33rd Chicagos Elevated Train System Turning 125

On June 6, 1892, the first ‘L’ line, South Side ‘L’ began service from Congress St. just south of what is now the Loop (which didn’t fully open for another five years) and 39th St. (now Pershing Rd.). This 125-year-old elevated railway is still in service as part of today’s Green Line (and Red Line during Red Line South Reconstruction) from near the S-curve at Harrison to just before the Indiana stop on Chicago’s South Side. This 1949 photo is taken from the former station at 33rd, looking south toward 35th. (Credit: Flickr/CTA)

The ‘L’ trains began running into the World Fair’s grounds May 12, 1893.

More elevated tracks were built by private companies over the next 10 years as the trains gained popularity – including the Lake Street “L,” which is now the Lake branch of the Green Line; the Metropolitan West Side “L,” which later became sections of the Blue Line and Pink Line; the Union “L,” which is now the iconic Loop; and the Northwestern “L,” which now makes up part of the Brown, Purple and Red Lines.

lake street l 1892 Chicagos Elevated Train System Turning 125

This undated photo at Rockwell shows part of the Lake Street ‘L’ under construction. Circa 1892. (Credit: Flickr/CTA)

Today, the CTA’s train system spans nearly 225 miles of elevated and subway tracks, with a fleet of about 1,500 cars, some still running on original sections of the 1890s “L” system. The CTA said approximately 750,000 people ride on elevated tracks each day.

To celebrate the 125th anniversary of the “L,” the CTA was passing out commemorative posters at the Clark/Lake station on the Inner Loop platform from noon until 3:15 p.m. Historic “L” cars built in 1923 and 1976 also will operate in the Loop between noon and 3:15 p.m.

Mayor Rahm Emanuel rode one a vintage 4000-series train from 1923 to the Garfield Station on the Green Line on Tuesday, for a celebration at one of the oldest stations in the U.S.

The Garfield station is set for a $50 million facelift, which will include restoring the original brick stationhouse, built in 1892 for the World’s Columbian Exposition. The stationhouse, which is no longer in use, received landmark status from the city in 2001, and will be reopened for a public use, such as a community space.

The renovation of the station also will include improvements to the elevator and escalators, extended platform canopies, new public art, enhanced landscaping, new benches, and an improved pedestrian crossing. The city also will add more bike lanes in the area to improve access to the station.

“The investments we’re making today, which are unprecedented in the history of the CTA system, will also reinforce that it will be around for the next 125 years,” Emanuel said.

Work on the Garfield station renovation is set to begin next year, and will be completed by 2019.

Watch & Listen LIVE