Just why does the Indianapolis 500 winner drink a bottle of milk? And other trivia from the Brickyard

Reporting from Indianapolis

Tradition is everything at the Indianapolis 500, from the singing of “Back Home Again in Indiana” before the race to the winner’s celebratory bottle of milk.

Here are a few bits of trivia about the Memorial Day weekend classic, which is celebrating its 100th anniversary this year, and the Indianapolis Motor Speedway.

Just how big is the track? It’s a rectangular, 2.5-mile track, and the speedway likes to note that Vatican City, Churchill Downs, Yankee Stadium, the Rose Bowl and the Roman Colosseum combined could fit within its 253-acre infield.

This is the 100th anniversary race but not the 100th race. Why? Because the race wasn’t held in 1917-18 and 1942-45 during the world wars.

How many spectators attend? The speedway has never disclosed its exact number of seats but says it’s more than 250,000, and there are several thousand people in the infield.

What’s with the milk? After three-time winner Louis Meyer drank buttermilk in Victory Lane in 1936, a milk industry executive made an effort to have future winners repeat the gesture, and it eventually stuck.

What did Dario Franchitti earn for winning last year’s race? $2.8 million.

Which drivers have won the most times at Indy? Three drivers have each won four times: A.J. Foyt, Al Unser Sr. and Rick Mears.

Who are the youngest and oldest winners? Troy Ruttman won at age 22 in 1952, and Al Unser Sr. was 47 when he won in 1987.

Who was the first woman to drive in the 500? Janet Guthrie in 1977.

Which drivers have won the race three consecutive years? None. The last to win two years in a row was Helio Castroneves in 2001 and 2002.

Do the cars run on gasoline? No, they run on ethanol.

Why is the track called the Brickyard? Early in its history, the speedway’s surface consisted of 3.2 million bricks. There is still a 3-foot-wide strip of the bricks at the start-finish line.

What does it cost to attend the race? General admission tickets start at $30. Grandstand seats mostly range from $70 to $150.

james.peltz@latimes.com