With the parking garages below, Millennium Park became the largest green roof in the world. It was the dream project, and a crowning achievement, of Chicago's longest serving mayor, Richard M. Daley.

Chicago’s $480 million Millennium Park, completed in 2004, is technically an intensive green roof, and one of the world’s largest at 24.5 acres.

Former Mayor Daley Recalls Vision For Millennium Park. October 9, 2012 / 6:26 AM CDT / CBS Chicago ... Now he says it's a global attraction over the largest green roof in the world.

NEW CATCH PHRASE was in the air after Frank Gehry’s shimmering Guggenheim Museum made its spectacular debut eight years ago in the tattered shipbuilding city of Bilbao, Spain: “the Bilbao ...

Using satellite images, researchers measured the affect of green roofs at Chicago’s Millennium Park, City Hall and a Walmart shopping center and compared the changes in land surface temperatures ...

NEW CATCH PHRASE was in the air after Frank Gehry’s shimmering Guggenheim Museum made its spectacular debut eight years ago in the tattered shipbuilding city of Bilbao, Spain: “the Bilbao ...

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.

Millennium Park, which has an intensive mix of plants and is located near Lake Michigan, showed significantly lower average temperatures after its green roof was installed in 2004.

Millennium Park, which has an intensive mix of plants and is located near Lake Michigan, showed significantly lower average temperatures after its green roof was installed in 2004.

Millennium Park is a can't miss attraction in Chicago and it turned 20 years old this week. Thursday, the city is kicking off a four-day celebration. ABC7 Chicago is now streaming 24/7. Click here ...