As Muhammad Ali’s youngest son rode in his father’s funeral procession through the streets of the city he adored, he noticed scores of children lining the route, pumping their fists, shouting “Ali! Ali!”

Asaad Amin Ali figured the children in attendance couldn’t possibly yet understand what they were experiencing Friday as Louisville and the world paid their respects to The Greatest.

“It’s not explainable, it was amazing,” said Asaad Amin Ali. “We looked out of the car and see people dancing and cheering and you also see people crying. (The children) are going to remember that for the rest of their lives.

“The outpouring of love … it’s inspiration. We saw how much he affected the world.”

Ali’s made one final journey through Louisville, his hometown, then was laid to rest in a cemetery he chose more than a decade ago. The burial was followed by a star-studded memorial service where the boxing great was eulogized as a brash and wildly charismatic breaker of racial barriers.

The more than three-hour memorial capped nearly a full day of mourning in Louisville for Ali, the three-time heavyweight champion of the world who died last week at 74 after a long battle with Parkinson’s disease.

Family spokesman Bob Gunnell said when the motorcade pulled up outside Ali’s childhood home, they were already woefully behind schedule. They hadn’t planned to stop there, just drive by and wave.

But the street was jammed full of people who threw roses on the cars. Ali’s widow, Lonnie, asked if they could pause there.

“Let’s just stay here for a few seconds and let Muhammad enjoy this,” Gunnell recalled she said.

They made their way to Broadway where it looked like the whole city lined the streets. Gunnell looked back at a car behind him and saw actor Will Smith, his hand hung out the window, giving high fives to kids on the street.

There was so much activity in the week since Ali died, his family has had little time to reflect.

“Things are going to slow down, we’re really going to have a chance to sit and think about his passing. It’s going to be a tough time,” said Asaad Amin Ali.

The memorial service was packed with celebrities, athletes and politicians, including former President Bill Clinton, Sen. Orrin Hatch, director Spike Lee, former NFL great Jim Brown, Arnold Schwarzenegger, soccer star David Beckham, Whoopi Goldberg and Kareem Abdul-Jabbar.

It was comedian Billy Crystal, though, who brought the house down with impressions of Ali and his memories of his time with the champion.

“He was a tremendous bolt of lightning, created by Mother Nature out of thin air, a fantastic combination of power and beauty,” said Crystal. “We’ve seen still photographs of lightning at the moment of impact, ferocious in its strength, magnificent in its elegance. And at the moment of impact it lights up everything around it so you can see everything clearly.

“Muhammad Ali struck us in the middle of America’s darkest night.”

Celebrities, politicians and athletes all came to honor Ali. But no one came out like the residents of his hometown, who put on a week of festivities to honor their most famous son.

More than 100,000 people filled the streets for The Champ’s final journey, which took a 19-mile route past Ali’s boyhood home and the museum that bears his name, via Muhammad Ali Boulevard.

Fans chanted like spectators at one of his fights, stood on cars, held up cellphones, signs and T-shirts, tossed flowers and scattered rose petals along the path of the hearse. Truckers honked their horns in salute. Others fell silent and looked on reverently as the champ went by.

“He stood up for himself and for us, even when it wasn’t popular,” said Ashia Powell, waiting at a railing for the hearse to pass by on an interstate highway below.

Takeisha Benedict and four co-workers were color-coordinated in orange “I Am Ali” T-shirts as they waited along Muhammad Ali Boulevard to pay their respects as the hearse went by.

“To me, he was a legend to this city and an example to people. I’m just glad to be part of this history of saying goodbye,” she said. “Opening it up and allowing us to be part of it, we’re so appreciative.”

Hundreds of people crowded the streets in front of the funeral home.

Mike Stallings, 36, of Louisville, brought his two young sons, and the family made signs to wave.

“I’ve been crying all week,” he said. “As big as he was he never looked down on people. He always mingled among the crowds.”

Ali designed the week’s remembrances himself, in a document so detailed it became known as “The Book.” He was steadfast in wanting it to be open to VIPs and regular people.

The services were streamed around the world, allowing all to watch “The Greatest’s” final chapter.

They witnessed moving tributes for the icon, and a joke from Clinton: “I can just hear Muhammad say now, ‘Well, I thought I should be eulogized by at least one president.'”

Kevin Cosby, pastor of a Louisville church, told the crowd that Ali “dared to affirm the power and capacity of African-Americans” and infused them with a “sense of somebodiness.” He likened Ali to such racial trailblazers as Jesse Owens, Rosa Parks and Jackie Robinson.

“Before James Brown said, ‘I’m black and I’m proud,’ Muhammad Ali said, ‘I’m black and I’m pretty,'” Cosby said.

“Blacks and pretty were an oxymoron.”

Rabbi Michael Lerner, a political activist and editor of the Jewish magazine Tikkun, brought the crowd to its feet four times with a fiery speech in which he referred to Ali’s refusal to be drafted during the Vietnam War — a stand that cost him his boxing title.

“Ali stood up to immoral war, risked fame to speak truth to power. The way to honor him is to be like him today,” Lerner said, railing against anti-Muslim bigotry, drone attacks, the gap between rich and poor, and racist policing.

President Barack Obama was unable to make the trip because of daughter Malia’s high school graduation. But White House adviser Valerie Jarrett read a letter from the president at the service in which Obama said Ali helped give him the audacity to think he could one day be president.

“Muhammad Ali was America. Brash. Defiant. Pioneering. Never tired. Always game to test the odds. He was our most basic freedoms: religion, speech, spirit,” Obama said.