The $303 million dollar project lasted more than two years and involved the section from Congress Parkway all the way north to Randolph.
Some people will say that unless you use Lower Wacker, you're not a true Chicagoan. For many, this is like the return of an old friend.
A wave of approval as a vehicle heads into the newly re-opened Lower Wacker Drive.
For many, it's a new downtown.
"It's just been interesting every morning trying to figure out which way, which path you're going to take to work," said pedestrian Alex Pichs. "So it's a lot more straightforward now."
At 8 a.m. Friday morning, workers removed the final barriers on Upper Wacker at Van Buren marking the end of the $300 million, two-year-long construction project.
"If you invest in your infrastructure, your roads, your rails, and your runways, there is nobody that will ever beat the city of Chicago when it comes to the modern economy," said Mayor Rahm Emanuel.
The new Upper Wacker is wider than the old one with reconfigured traffic signals and larger sidewalks and crosswalks for pedestrians.
"Now, you've got something that's much more modern, next generation, safer," said Chicago Department of Transportation Commissioner Gabe Klein.
By mid-afternoon, Lower Wacker was fully-open, as well, re-connecting Lakeshore Drive to the congress interchange and the Eisenhower Expressway.
The new Lower Wacker has improved lighting, a higher ceiling and fewer ramps.
"Those zero clearance merges are gone," said CDOT chief engineer Dan Burke. "It's much safer, modern corridor now. So it's a great amenity for everyone who uses it."
The two-year long construction project created or supported more than 3,100 jobs but it also hurt some nearby businesses.
"We've kind of just changed up our lunch spots," said pedestrian Candice Gora. "So we haven't been going to some of these businesses down here."
A parking lot at Wacker and Van Buren was once again full and so are some nearby eateries.
"It will definitely pick up quite a bit, which will be nice," said NYC Bagel Deli's Jamal Semaan. "And we're really excited to have all the people come down."
The pavement is made of concrete, which has a little bit longer of a lifespan compared to asphalt, which is what the old Wacker Drive was made up of.
Officials say the lifespan on the new Wacker Drive is 70-100 years.