Saturday's moderate temperatures helped bring out the crowds for the city's St. Patrick's Day celebrations.
"Today is amazing," Brenda Dulaney said. "Walked out, sun is shining. If you are a Chicagoan, you know this is the best weather you can have now in March."
As many as a million people were estimated to have attended the 59th Annual Chicago St. Patrick's Day Parade, which stepped off at noon at Balbo and Columbus and wound north on Columbus.
"It's becoming such a huge tourist attraction for Chicago. So I think the hotels are going to be full and the establishments are going to be full today," Jim Coyne, the chairman of the St. Patrick's Day Parade, said.
Chicago Mayor Rahm Emanuel helped lead the procession of more than 160 groups, including bagpipers and Irish dancers.
"It's really, really lively," Kyle Lilly, parade goer, said. And so are the revelers, many of whom got up early to watch the Chicago River turn green just hours before.
Chicago River dyed green
What causes the Chicago River to turn green for St. Patrick's Day? That is a secret only the Chicago Journeymen Plumbs Union Loal 130 knows. They dumped containers of dye from motorboats in to the Chicago River at 9:30 a.m. Saturday. It's been a tradition since 1962.
"To see how they mix it up and do it, and the history of it, thousands of people, it's outstanding," said Tom McCarthy. "It's better than the parade. You can watch the parade of Channel 7, but here, you have to see this live."
Dyeing the Chicago River a beautiful emerald green has been a tradition for many generations and attracts hundreds of thousands of people dressed in their best St. Patrick's Day apparel.
Revelers come early to get the best spots.
"It's just a sense of community, when everyone has something to rally around it just brings everyone together; it's why we come," said Ashley Buchler.
The Cooks had no clue what they were in for.
"Our kids gave us a trip to Chicago for Christmas, they planned everything. We didn't choose this weekend, they did and we didn't know so when we found out we went ballistic," Becky Cook said.
They are so excited to be part of such a rich, albeit a little chilly, tradition.
"We're early enough," said Ron Cook. "We got a nice sunshine and it's what, 33 degrees? So it's not bad out here."
The river's green color lasts for six to 12 hours, but the St. Patrick's Day celebration tends to linger well into the night.
A second parade takes place Sunday on the city's South Side.