LOUISVILLE - More than 100,000 people lined the streets of Louisville on Friday to watch a 17-car procession drive Muhammad Ali's body to Cave Hill Cemetery.

The procession was scheduled to begin at 9:30 a.m., but didn't get underway until after 10:30 p.m. and last more than three hours.

Prior to the procession, a family spokesman announced there would be one word on his headstone. Simply: "Ali."

Family spokesman Bob Gunnell said the simple stone is in keeping with Islamic tradition.

A memorial service later in the day was pushed back to 3 p.m. at the KFC Yum! Center due to the late start.

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The procession arrived at Cave Hill Cemetery after its journey through Louisville, where people lined the streets, chanted "Ali, Ali," and three flowers on the hearse.

The event at the cemetery was private -- closed to the public and media. Following his burial, Ali's family and friends will make their way to the KFC Yum! Center in downtown Louisville for a public memorial service.

The procession passed a number of important landmarks for Ali as it made its way through Louisville, including a brief pause in front of his boyhood home.

Ali's family and friends in the motorcade rolled down their windows to greet the crowds lining the streets near the house where he was born. They could be seen waving out of the windows.

Prior to that, the procession stopped for 30 seconds outside the Ali Center, where a mosaic showed Ali's face, and people lined the rooftop and freeway.

From there, the hearse and other vehicles left the interstate to move through city streets. The procession was expected to pass the African-American Heritage Center next.

Thousands of people from around the world lined the streets of Louisville -- an estimated 100,000 plus -- for the procession.

That included heads of nations, who have contributed to the makeshift memorial growing outside the Muhammad Ali Center.

A wreath of red roses was signed from the Prime Minister of Pakistan, Mohammad Nawaz Sharif. A garland of white flowers came from the ambassador of Bangladesh.

Others left prized possessions: a framed copy of a Sports Illustrated with Ali on the cover, a hand-painted canvas of Ali's likeness, framed photos of children with the Champ.

PHOTOS: Funeral procession for Muhammad Ali

Pallbearers loaded Muhammad Ali's body into a hearse outside a funeral home in Fern Creek just before 10:30 a.m. on Friday before the motorcade departed on a 21-mile route.

The hearse carrying Ali's body was followed by a car with Lonnie, Ali's wife.

Ali chose Cave Hill Cemetery as his final resting place a decade ago. Cave Hill is on the National Register of Historic Places, and also the final resting place of Kentucky Fried Chicken founder Colonel Harland Sanders.

Ali wanted to be buried in his hometown, where he learned to box and fought his first fight. He also built a museum and the city named a street in his honor.

RELATED: Noted participants in Ali's service

A number of notable people are expected to attend and take part in the service for Ali, including former President Bill Clinton, actors Billy Crystal and Will Smith, and Mike Tyson.

Tyson was a late addition as a pallbearer at Muhammad Ali's burial, joining a group that included Smith and another former heavyweight champion, Lennox Lewis.

Ali family spokesman Bob Gunnell said Tyson caught a late flight to be part of the ceremonies Friday. Gunnell said Tyson wasn't sure if he would attend the service because of a prior commitment.

Tyson was highly emotional when he learned of Ali's death and wasn't sure if he could handle the emotions of Ali's memorial, Gunnell said.

Kareem Abdul-Jabbar was spotted at the Ali Center early Friday morning paying tribute to his dear friend.

Gunnell said Friday morning that 300 celebrities and dignitaries will be among the 15,500 in the crowd.

Beyond the dignataries who traveled to town, average people came from near and far to show their respect.

One family, the Pinnocks, came from Toronto. When Adam Pinnock was 5 months old, he met Ali. The family came to honor his memory and to be part of the moment.

PHOTOS: Remembering the Greatest in Louisville

People gathered early outside Muhammad Ali's boyhood home, which was decorated with balloons, flags, flowers and posters for Friday's memorial.

Fans took photos of themselves standing in front of the small pink home with white trim, and standing near a large cloth poster on the lawn decorated with images of Ali, and declaring him "The Greatest."

Some people staked out their place near the home with lawn chairs. Others milled about on foot.