LOUISVILLE, Ky. - Muhammad Ali is turning 70, but the boxing great is still a "big kid" who enjoys his birthday parties, his wife said.

The three-time heavyweight champion reaches the milestone Tuesday, but the festivities will start early. Ali will be surrounded by friends who are gathering Saturday evening for a private birthday party at the Muhammad Ali Center in his hometown of Louisville.

"Muhammad likes celebrations that involve him and are centred around him," Lonnie Ali told reporters before giving a speech Friday at the Ali Center. "He's still a big kid in that area. He loves birthdays."

Lonnie Ali said it's the first of five parties for her husband over the next couple of months. Other parties will be in Las Vegas, California and Arizona, she said.

"That's the way to celebrate your 70th," she said.

She said the champ will be surrounded by close friends and people who have been fixtures in his life at the party Saturday night, including his famed trainer Angelo Dundee. The party is doubling as a $1,000 per person fundraiser for the centre, a cultural and education complex that also features a museum focusing on Ali's long career as a boxer, social activist and humanitarian.

"The lessons this man knows innately ... are the things we're trying to pass on to future generations, to encourage them to be great and find greatness within like Muhammad as a young man here in Louisville," Lonnie Ali said.

Cynthia White, who travels the world through her job with the Louisville-based Presbyterian Church (U.S.A.), said Ali's influence remains powerful in remote places around the globe, decades after his boxing career ended.

White, who attended Lonnie Ali's speech, afterward recalled visiting a village in Uganda several years ago. When people found out she was from Louisville, a young boy started shadowboxing and chanting Ali's name, she said.

"Muhammad Ali is still a real force in the lives of children and adults around the world," she said.

Born as Cassius Marcellus Clay Jr. on Jan. 17, 1942, he grew up in a predominantly black West End neighbourhood of Louisville. He took up boxing at age 12, later becoming a top amateur boxer and Olympic gold medallist .

Ali, raised in a Baptist family, announced his conversion to the Muslim faith and changed his name after defeating Sonny Liston in 1964 to win the heavyweight crown for the first time. He moved to Miami in the early 1960s but kept his close ties to Louisville, where he has a home today. The Alis also have homes in Michigan and Arizona.

Ali was stripped of his boxing title in 1967 for refusing to go into the Army during the war, citing his religious beliefs.

"In the face of adversity, this man just perseveres," Ali's wife said of her husband during her speech.

Ali, who is battling Parkinson's disease, is largely absent from the public eye now.

Befitting his celebrity status, Ali's party Saturday evening will include performances by singer John Mellencamp and others.

The guest list includes NBC journalists Matt Lauer, Ann Curry and Bryant Gumbel, Academy Award-winning director Leon Gast, three-time heavyweight boxing champion Lennox Lewis, University of Louisville basketball coach Rick Pitino and University of Kentucky coach John Calipari.

Also invited to the celebration were Josh Fattal, Shane Bauer and Sarah Shourd, three American hikers who were imprisoned in Iran. Ali sent a letter to the Iranian government asking for the trio's release.

Lonnie Ali said the boxing legend has mixed feelings about the landmark birthday.

"He's glad he's here to turn 70, but he wants to be reassured he doesn't look 70," Lonnie Ali said.

The couple chose Louisville and the Ali Center for the first party because, "this is his home. This is where he started. These are the people who supported him," Lonnie Ali said.

Even with all the planning for the birthday celebration, Lonnie Ali is still unsure what to get her husband.

"It's hard to get something for someone who has everything," she said.