Thursday, the city is kicking off a four-day celebration.
Millennium Park opened July 16, 2004. It was built on top of parking garages and commuter rail lines and it's considered the world's largest rooftop garden.
Millennium Park is part of the iconic imagery that sells Chicago to the world. 20 million visitors come to the park every year, whether it is to enjoy a free concert, relax by Crown Fountain or just to take a picture at the Bean, but it wasn't always like that.
Then-Mayor Richard Daley was driving force behind the massive project.
"When the Mayor conceived of this, he saw the railroad tracks, and it was true, as this barrier between Chicagoans in the Loop and enjoying the Lakefront and not having direct access," said Eleanor Gorski with the Chicago Architecture Center.
Millennium Park used to look very different in the 90s, with 24 acres of train tracks and parking lots owned by the Illinois Central Railroad. It was, according to legend, the view from then Mayor Richard Daley's dentist's office-that sparked in him the desire to reclaim the land for the city.
There is really no way to disguise it. Except if you get the air rights and you build over them. Which is exactly what happened," Gorski said.
Even as the city broke ground on Millennium Park, the project ran into obstacles, opening four years behind schedule and $340 million dollars over budget. As it turns out, one of the park's most iconic features, Pritzker Pavilion, almost never happened, at least not in its current form.
"Cindy Pritzker had offered a generous donation to the project, but she caveated it with you have to bring in Frank Gehry, because we want a Frank Gehry design in the City of Chicago," former Millenium Pakr project manager Paul Clausen said. "So they said, 'fine.' They reached out, and he turned the project down."
Fortunately for Chicago, Gehry was eventually talked into it, but the project as a whole kept running into delays. By the time Architect Paul Clausen was brought in as project manager, Millennium Park was already well behind schedule. Much of the challenge, he said, was in the revolutionary nature of the engineering itself.
"When we brought it into the building department to get it permitted, they were shocked," Clausen said. "They had never seen this kind of thing before. He's flipping his eyes kept getting bigger and bigger at what we were proposing to build."
Millennium Park is now one of the largest green roofs in the world. It's presence has transformed the entire area, bringing along with it a new neighborhood, River East.
"It really was a public, private partnership, and that's the best part of the story, where you had the civic community and corporations and foundations basically paying for half the park," Gorski said.
The lakefront campus in the heart of downtown is home to the iconic Cloud Gate statue also known as The Bean, where people from all over the world come to take pictures.
Millennium Park is of course filled with interactive fountains, greenspace, tranquil gardens, public art, skating rinks and the Pritzker Pavilion, which hosts free concerts.
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In 2015, Millennium Park also became the location of the city's annual Christmas tree lighting.
Millennium Park's significance is great to visitors and residents alike.
"It's great for the residents but it draws an international crowd and that's very, very important for a city like Chicago to be on the international map for tourism and it also shows that we care for our city and our continually revitalizing the park, programming it," Eleanor Gorski, Chicago Architecture Center CEO, said.
The Chicago Department of Cultural Affairs operates the public park and is hosting a free four-day millennium park 20th anniversary celebration which runs Thursday through Sunday featuring performances, activities and fireworks.
Thursday night, the celebration kicks off with Sueblo presenting an evening highlighting the musical tapestry of Latin culture on the Jay Pritzker Pavilion stage. That got underway at 5 p.m.
Friday night, the Chicago Symphony Orchestra will perform music from the movie "Star Wars and more.
The free vents are all to say "Happy Birthday" to Millennium Park.
List of events:
Thursday
-¡Súbelo! will present an evening highlighting the musical tapestry of Latine culture on the Jay Pritzker Pavilion stage.
-Chuwi, a tropical, indie fusion quartet from Puerto Rico merging salsa, boleros, and folk music with flashes of alternative Hip Hop, psychedelic, and electronic.
-Codigo FN,hailing from Sinaloa, Mexico, this Mexican Regional group debuted with intensity on the Billboard charts.
-Fruko y Sus Tesos with special guest Sonora Dinamita featuring Alfredo de la Fe. Acclaimed Salsa band from Colombia Fruko y Sus Tesos performs as part of their 60th anniversary tour.
Friday, July 19
- Grant Park Orchestra will perform Star Wars and More: the Music of John Williams. Enjoy iconic musical selections- costumes welcome.Saturday, July 20
--A full slate of events, culminating in Chicago native, rapper and actor Common performing with the Grant Park Orchestra, followed by a fireworks display.
-Millennium Park Summer Workouts with Pilates and Yoga
-Family-friendly artmaking with Somos Arte in the North Promenade Tent.
-Chicago Physical Theater Festival performances featuring the Chicago Boyz Acrobatic Team, Alexander D'Amazing, Eric Robinson, and Stephanie Diaz with Gaby Diaz, sharing acrobatic displays, clowning and spectacle, trampoline feats, cicada puppets and more in Wrigley Square.
-Dance performances in the North Promenade Tent
-INT'L CAFE sparks opportunities for cultural exchange by connecting language speakers/signers of all levels for immersive conversations with new friends in the North Promenade Tent.
-Heart of Chicago Soul Club spinning all vinyl, rare and Northern Soul, with Northern Soul Dancing taught by Miss Wolff's Jiving School in the North Promenade Tent.
-Eli's Giant Cheesecake celebrating Millennium Park's 20th Birthday at Cloud Gate. Join the celebration and enjoy free cheesecake.
-A roving performance by Los Pleneros de Don Segundo with horns, vejigantes, cabezudos, and stilt walkers.
-Pop-up Performances by South Shore Drill Team and Ballet Folklorico de Chicago at Cloud Gate.
-Common will perform with the Grant Park Orchestra
-The evening will culminate with a fireworks display to celebrate Millennium Park's 20th Anniversary.
Sunday, July 21
--The final day of 20th anniversary programming brings a full day of family-friendly activities, plus a dynamic evening concert featuring an array of award-winning performers as part of the "The S&S Chicago Experience," curated by Steve "Silk" Hurley and Shannon "Skip" Syas.
-Family-friendly programming in North Promenade Tent, Crown Fountain, and Wrigley Square.
-Story hour for families at Crown Fountain.
-The Golden Horse Ranch Band family square dance for all ages in the North Promenade Tent.
-Interactive Drum Circleand instrument making led by Rhythm Revolution at Crown Fountain.
-Wonder Wagon brings large, colorful puppets to Wrigley Square with opportunities for hands-on interaction.
-Dance performances from Chicago artists in the North Promenade Tent.
-INT'L CAFE sparks opportunities for cultural exchange by connecting language speakers/signers of all levels for immersive conversations with new friends in the North Promenade Tent.
-Sonorama DJ collective with free dance lessons in Salsa and Cumbia and open dance party featuring vintage Latin sounds in the North Promenade Tent.
-The S&S Chicago Experience at the Jay Pritzker Pavilion stage curated by Steve "Silk" Hurley and Shannon "Skip" Syas