INDIANAPOLIS (AP) — Long before he won the Indianapolis 500, Al Unser was an up-and-coming 25-year-old sprint car driver who had showed up at Indianapolis Motor Speedway to watch his older brother try to qualify.
Unser still remembers the feeling of awe when he drove through the tunnel beneath the track.
''I had never seen such large grandstands,'' he said, ''filled with so many people.''
More than 50 years later, and after four triumphs and so many other unforgettable races at Indy, Unser's first look at the historic speedway in May 1964 remains his most memorable moment there.
In the lead-up to the 100th running of the ''The Greatest Spectacle in Racing,'' The Associated Press interviewed the 27 living race winners on topics ranging from the best driver to greatest tradition.
When asked for their most memorable moment, several recalled their earliest memories,
''The biggest thing I really remember was sitting up in the grandstands of Turn 1, and you are just enjoying the time with my mom and dad and the beautiful weather and watching cars,'' said 2006 champion Sam Hornish Jr. ''One of those was (Danny) Sullivan spinning and winning it (in 1985). So that wasn't bad.''
Hornish doesn't remember much of his own victory, when he edged Marco Andretti in one of the closest races in history. Everything was too much of a blur: getting pushed into victory lane, pouring the milk over his head, spending the next three hours taking photographs with the Borg-Warner Trophy.
But for many other former champions, winning the race remains their moment second-to-none.
''No question, there's nothing that can match seeing the checkered flag,'' said 1969 winner Mario Andretti. ''It's just a huge weight off your shoulders because you know how important it is to your career.
''It's like if you didn't win that, you're a wanker or something. That's the saddest part about it, quite honestly,'' Andretti explained. ''That's the way it is and that's what you've got to deal with. But seeing the checkered flag, in my case - yes, that's the most memorable moment for me.''
Bobby Unser chose the first of his three victories in 1968, in part because everyone thought the turbine cars would dominate. One by one they fell away, leaving Unser to battle Dan Gurney for the win.
Gordon Johncock remembers dueling with Rick Mears in the closing laps in 1982, holding off the eventual four-time winner in what is still regarded as one of the greatest races in history.
Parnelli Jones can remember his 1963 triumph like it happened last week.
''It was just a tremendous thrill,'' he said. ''You work so hard to get there. I woke up early the next morning and looked in the mirror to make sure I wasn't dreaming. The Indy 500 makes you.''
Yet even the best drivers to run at Indy, those who succeeded in reaching victory lane, are fans of the sport. They can appreciate a side-by-side duel on the final lap, or a particularly epic save - like Sullivan's spin-and-win - or a particularly emotional moment made all the more poignant by time.
Dario Franchitti did not choose one of his three victories as the most memorable moment, but instead the 2011 victory for Dan Wheldon. It came after J.R. Hildebrand crashed in the final turn, allowing Wheldon to win for his small and underfunded team, and just months before Wheldon died in a wreck in Las Vegas.
Jacques Villeneuve called the epic 1992 finish between Al Unser Jr. and Scott Goodyear, still the closest in race history, the greatest moment. Unser won the first of his two championships by 0.043 seconds.
Eddie Cheever won the Indy 500 in 1998, but it was a moment at the Brickyard five years earlier that stands out to him: ''A.J. (Foyt) retiring at Indy. Even he got teary.''
Yes, the hallowed grounds of Indianapolis Motor Speedway can reduce even the most hardened of Texans to tears. It is part of the majesty of the place, the mystique that has made it such a part of Americana.
''Driving onto the track in an Indycar for the first time,'' Unser Jr. said, when asked for his memorable moment. ''It was a childhood dream of mine coming true. I was overwhelmed.''