Two years ago, USA Today polled its readers for their bucket lists of sports events they most wanted to attend at least once.
The top vote-getter wasn't the Super Bowl or the Masters or the Olympics.
It was the Indianapolis 500.
The iconic race returns Sunday for the 100th running of the Memorial Day weekend classic, which draws more than a quarter of a million spectators captivated by its s speed, danger and tradition.
Indianapolis Motor Speedway said Sunday's race is sold out. The track doesn't divulge exact numbers for spectator capacity, but the number of grandstand seats is about 250,000 and the track reportedly sells at least an additional 70,000 infield general-admission tickets.
There's plenty of room. The speedway likes to boast that the Rose Bowl, Yankee Stadium, Vatican City, Churchill Downs and more would fit inside the massive infield of the 2.5-mile rectangular track that sits in a residential neighborhood.
The speedway claims that the race is "the largest single-day sporting event on the planet."
The speedway -- dubbed "The Brickyard" because long ago it was paved with 3.2 million bricks -- also said it has suspended its practice of blacking out the race on local television in Indianapolis. It's the first time since the early 1950s that the race will be televised live in central Indiana.
"There's no event like the Indianapolis 500 and for the event to sell out on the occasion of the 100th running is a testament to the enduring legacy of 'The Greatest Spectacle in Racing,'" Mark Miles, chief executive of track owner Hulman & Co., said in a statement.
The Indianapolis 500 has remained one of the nation's preeminent sporting events despite a 12-year civil war between the sport's leaders that ended in 2008, a decline in the popularity of IndyCar racing overall, a dearth of American drivers and a long history of tragedy on the track.
"The Indy 500 is part of the beautiful essence of America," said 1998 Indy 500 winner Eddie Cheever, now an analyst with ABC, which televises the race. "Wherever I am in the world, I never have to explain to people what it is. They know."
For the 33 drivers in the race, many say they would rather win the Indy 500 than the championship of the Verizon IndyCar Series, a stance heightened by knowing this is the race's 100th running.
"This place makes careers and changes lives," said Ed Carpenter, an Indianapolis native and driver/team owner who sat on the pole in 2013 and 2014 and who starts 20th this year. "It's been my dream to win this race for a long, long time."
Veteran Tony Kanaan, 41, a fan favorite who finally won his first Indy 500 in 2013, said the Indianapolis speedway "is magical" and that the "buzz around the city, it's unbelievable" this year.
"I thought I had seen it all, but I haven't seen this place sold out," Kanaan said.
The first Indianapolis 500 was held in 1911 and won by Ray Harroun. The race has been held ever since except during six war years: 1917-18 and 1942-45.
This year's race already has one heartwarming story: James Hinchcliffe, the 29-year-old Canadian who nearly died from injuries in a practice crash a year ago, won the pole position during qualifying last Sunday.
Indeed, though motor racing inherently is dangerous, the threat is magnified at Indianapolis because of the high speeds.
Hinchcliffe won the pole with a four-lap average of 230.760 mph, and at some spots on the speedway the cars surpass 235 mph, traveling the length of a football field in about one second.
There have been 38 drivers who died from crashes during the race or in accidents in practice and qualifying during May, according to the speedway historian.
But owing to advancing safety improvements in the cars, drivers' gear and at the track, including so-called SAFER barrier soft walls, there hasn't been an Indy 500-related fatality in 20 years.
The last was Scott Brayton, who was killed during a practice crash in 1996. The last driver to die from injuries sustained in the race itself was Swede Savage in 1973.
Roger Penske, who by far holds the record for the most Indy 500 victories for a team owner, with 16, is hoping one of his drivers wins the 100th edition of the race in the same year Penske is celebrating his 50th anniversary in racing.
Penske, who will drive the pace car for this year's start, is "still the one that sets the bar," said rival team owner Chip Ganassi.
The betting public is on Penske's side as well. His four drivers -- Will Power, defending Indy 500 winner Juan Pablo Montoya, Simon Pagenaud and three-time Indy winner Helio Castroneves -- have the best odds to win Sunday, according to the gambling website Bovada.
Castroneves is trying to become only the fourth driver in history to win the race four times. The others are A.J. Foyt, Al Unser and Rick Mears.
The drivers have one final practice Friday on so-called Carb Day, a throwback term to the days when mechanics would make final adjustments to carburetors on the cars' engines. The Indy 500 is scheduled for 9 a.m. PDT/noon EDT on Sunday.
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