The Indy 500 is the "greatest spectacle in racing."

2011 marked the 100th anniversary of the Indianapolis 500 and 2016 marks the 100th running of the race itself. 

Traditions:

https://www.indianapolismotorspeedway.com/events/indy500/history/indy-500-traditions-faqs/traditions

• "Back Home Again in Indiana" 

 This song has been sung on the morning of race day every year since 1946.

 Jim Nabors is usually the one to do it.

• Balloons

They have released balloons before the race every year since 1947, and have done it in time with Back Home Again in Indiana since 1950.

• Milk

 It started because Louis Meyer drank milk out of habit and happened to do so in Victory Lane in 1936. The Milk Foundation made it tradition.

• the trophy

This trophy has been given to the winner of the race since 1936. It has the face of every winner since then on it. In the 1980's the last space was filled so they added a base to the           trophy so they could fit more winner's faces.