INDIANAPOLIS — Larry Walker will be here Sunday, just like every Memorial Day weekend for the past 60 years. From his sun-bathed perch high in the Northwest Vista, he’ll watch with excitement as 33 cars race toward him from Turn 1 to begin the 100th Indianapolis 500.

Walker, 69, knows he could be performing this rite of spring for the final time. And it saddens him. So does the fact that scores of his friends, long-time ticketholders around his age, have told him they won’t return after reaching this milestone installment, either.

“I have neuropathy in my leg and the walk is starting to wear at me,” Walker told USA TODAY Sports. “This is what I keep hearing from friends of mine — after the 100th running, they’re not coming back. I’m hearing it a lot. Times have changed.”

Indianapolis Motor Speedway is at a brick-paved crossroads.

In one direction is the path to the future vitality of the 107-year-old track and its continued place as one of America’s great sporting cathedrals. In another is a slow but unyielding road to ruin.

No doubt, Sunday’s race is a hallmark moment in the history of the venue at 16th and Georgetown. But the 101st might be more important as an indicator of whether it becomes a revitalized center of a revitalized sport or a fading icon. The turnstiles will decide it.

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Those prospects occupy the people charged with taking care of the speedway’s present and future, and those whose indelible memories of the place help form its glorious past.

“A hundred years is sort of a tent pole year, and that’s why we’ve all along tried to position it as ‘This isn’t an ending point, this is just one more in what has so far been 99 really important events,’ ” IMS President Douglas Boles told USA TODAY Sports. “The hundredth will be an important one. So will the 101st.”

Theory on the future of IMS is like religion in Indiana because connections with the 2.5-mile track are so personal for devotees tracing bloodlines back decades to afternoons under blue skies, pork loin sandwiches, whatever was in the cooler and (Back Home Again in) Indiana raising goose bumps on skin just beginning to sunburn.

Everywhere there is seemingly an anecdotal uncle from Bloomington or Terre Haute who fell in love with the racing when Parnelli Jones and Mario Andretti were forging legends. He has attended every race since the 1960s, trudging toward the 100th running like some elephant graveyard, whereupon he can finally rest, either too old or too infirm or just too out-priced and disgusted with the hassle of it all.

Walker, who says he’ll be attending his 62nd Indy 500 on Sunday, said his $109 tickets are expensive but a bargain compared to the nearly $300 he expends each game for season tickets to the NFL’s Indianapolis Colts. He remains an ardent racing fan, but he’s part of a shrinking and aging minority in a city whose fabric would seemingly be made of checkered cloth. Walker, a custom home builder who once owned 200 tickets a season but has whittled his allotment to 58, struggles to give away the last ducats, especially to anyone not in his 50s, he said.

“(The Indianapolis 500) has done so well because of the age group of, say, from early 50s to mid-70s, (but) we’re all getting old, not able to get around and we’re dying off,” he said. “The kids coming up don’t care.”

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Walker and Boles appear to be speaking to different fans. Boles said that repeat customers are the main driver of the audience each year, and he has spoken with a few subscribers who said they will not return after this running. A mass exodus of long-time subscribers, each eliminating multiple-ticket accounts from the stands, could produce a stark reduction in attendance from Sunday to whatever 2017 generates. Boles’ hope is that fans who do not renew will pass the mantle of ticker buyer to the next generation as it had been to them.

“When I talk to folks, especially ones who have been long term, there are people who are getting to the point where coming with 400,000 people in a venue and parking and walking is taxing,” Boles said. “But those are the same folks who have introduced their kids and their grandkids to the event. And those tickets, as people decide they’re done, typically, they have that next generation of the family that picks them up and continues to move forward.”

IMS officials would not reveal demographic data from its subscriber base, including average age of account holders and their ticket allotments. Since January, Boles has attempted to make roughly 10 calls daily to some of the 235,000-plus who have purchased grandstand tickets for the race this year, targeting those who purchased that day, renewed tickets for seven to 15 years and long-term buyers.

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“It’s interesting, especially to someone who is brand-new, the excitement around it, and how they want to be here for the hundredth and they followed IndyCar racing but never felt that magnet of, ‘Oh, I’ve got to go see this one,’ ” Boles said. “And then I think there are a lot of conversations where there are people who have gone for 20, 30, 40 years and then quit going for whatever reason. Life change, kids, whatever. For them to come back is exciting.

“So we have to deliver that experience when they get here, both on track and off that makes them say, ‘You know what? This is what I am going to continue to do on Memorial Day weekend.’ That’s how we try to keep that momentum going. It’s a great opportunity for us.”

Old fans, new fans

Fans will cram the sold-out race Sunday, with the throng of about 350,000 — including 235,000 in the grandstands — poised to be the largest since the sport’s apex before the acrimonious CART-Indy Racing League split in the mid-1990s. There will be an opportunity there, Zak Brown, Group CEO of CSM Sport & Entertainment, told USA TODAY Sports.

“IndyCar is growing,” he said. “Attendance and television is up and competition is great, and with the 100th running of the Indy 500, they have a real opportunity to convert new fans. Demand is the highest I’ve ever seen it at Indy since I’ve been in the business.”

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But a milestone Indy 500 is not the only potential indicator of the speedway’s momentum. A lengthy “Centennial” period that began in 2009 with commemorations of the anniversary of its opening is concluding. The final NASCAR season for transplanted Hoosier and four-time Sprint Cup champion Jeff Gordon spiked sales for the Brickyard 400 last July as he was central to the track’s marketing campaign. Native son Tony Stewart will enter his final edition of the Cup race this season — albeit in a more understated manner — removing one more natural hook for a local fan base that has become increasingly tepid toward what once was a marquee event.

“When you think about it from the Brickyard standpoint, our ticket sales were better than they had been for a long time (in 2015), and we attribute a lot of that to Jeff Gordon,” Boles said. “We got a little bit of that with the Tony Stewart effect. I think Tony not running (the first eight races because of an injury) made it a little harder for us to grab that moment and surround that particular event.”

Track officials say there is no evidence of a potential ticket-buying hangover for the 500, but one could come soon. Boles said traditionally 70% to 80% of ticket subscribers renew for the following year and most of those do it in the two weeks after the event.

“(Non-renewals) is a risk, but I’ve had very few conversations with people who have said to me, ‘I’ve come for 50 years and I’m going to be at the hundredth and I’m not going to come back,’ ” Boles said.

Walker understands the difficulty speedway officials face, specifically that the sell has become harder.

“I’m not saying they’re morons and they don’t know what they’re doing,” he said. “That’s not the case. Times have changed, and they’re grasping at straws.”

‘Tradition you can’t buy’

A.J. Foyt knows about American classics. He was the first driver to win the Indy 500 four times — a record shared with Al Unser and Rick Mears — the Daytona 500 and the Rolex 24 twice, but he said despite NASCAR’s advantages in market share and popularity and the grandeur of a revitalized Daytona International Speedway, the Indianapolis 500 remains paramount.

Stunned that he lived to see the 100th edition of the race that “made me,” Foyt said its future is secure. It will continue to define its time, he said.

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“Indianapolis is like the Kentucky Derby,” he said. “You can have the sorriest horse alive. If he wins one race, if he wins the Derby, he’s a Kentucky Derby winner, and that’s the same way with Indianapolis. Daytona is great, it’s beautiful, I enjoyed it, but it’s not Indianapolis.

“It’s tradition you can’t buy.”

Foyt’s analogy works on more levels than he might realize, some that could worry the IndyCar community. The Kentucky Derby has survived for 142 installments as the nation grew from an agrarian to mechanized society and horses became more of a nostalgic remembrance of a bucolic past than a relevant part of the present. Horse racing as a sport and as an industry captures the American fancy for generally no more than the first Saturday in May except when a 3-year-old reaches the Belmont Stakes with the opportunity to win a Triple Crown.

Similarly, open-wheel racing, its supremacy ravaged by fractious politics that resulted in the creation of rival but diminished series until reunification in 2008, and the opportunistic ascendancy of NASCAR, captivates the mainstream at the end of May, but battles for relevance before and after. Being a part of Americana is a wonderful thing, except when formulating a sustainable, 12-month business plan.

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“Highlighting its history and tradition matters, but so, too, does the overall positioning of the sport the other 364 days (of the) year, especially given the clutter this time of year with so much going on,” said David Carter, executive director of the Sports Business Institute at the University of Southern California. “Successfully leveraging its history, when complemented by the positioning and featuring of the drivers as the sport utilizes new forms of media to captivate (young) fans, is vital.”

Television ratings have improved relative to poor showings in recent years but have not matched the earnest insistence of competitors and series officials that IndyCar’s product is as worthy as it has ever been.

“I’ve always felt, and I think a lot of us have, that the hardest part is getting them to come to a race whether it’s Indy or anywhere,” said driver/team owner Ed Carpenter, whose stepfather, Tony George, is a member of the family that owns IndyCar and IMS. “And I meet more people who have a better experience than not.

“I don’t think anyone expects the 101st to have the exact same attendance as this year, but I’ll be shocked if it’s not bigger than what last year’s was. The product is good, the experience is great. I think we’re going to capture people. That’s just here. Hopefully the buzz that’s generated from a TV standpoint will kind of invigorate us moving forward.”

At least now, the moment could be primed for a series whose sense of timing has been, at times, self-defeating.

“I think (this) opportunity couldn’t come at a better time because I think we’re in a position as a series to take advantage of it,” Rahal Letterman Lanigan co-owner Bobby Rahal said. “I look at this as our opportunity to use this as a springboard to the future, not as ‘This is it. It’s not going to be this good again.’ ”

The prospect of a return to the grand times — with his son and driver, Graham a part of it — made the 1986 Indy 500 winner smile.

“I know it’s going to be nuts, crazy, huge,” Rahal said. “But I’m probably understating it.”

The moment and the opportunity.

Follow James on Twitter @brantjames