500 Festival Parade

Due to the longevity of the Indianapolis 500, numerous traditions surrounding the race have developed over the years. Traditions include procedures for the running of the race, scheduling, and pre-race and post-race festivities. For many fans, these traditions are an important aspect of the race, and they have often reacted quite negatively when the traditions are changed or broken.

As part of the Memorial Day holiday weekend, the pre-race ceremonies of the Indianapolis 500 feature several patriotic songs. The most noteworthy and most popular traditions are the annual singing of "Back Home Again in Indiana," and the victory lane bottle of milk.

The race has always been scheduled in conjunction with Memorial Day. Through 1970, the race was held on Memorial Day proper (May 30), regardless of the day of the week, unless it fell on Sunday. In those cases it was scheduled for Monday May 31. After the Uniform Monday Holiday Act took effect in 1971, the race was scheduled as part of the three-day Memorial Day weekend instead, either the Saturday, the Sunday, or the Monday. Since 1974, the race has been scheduled for the Sunday of Memorial Day weekend, and has been held on Sunday with only two exceptions due to rain delays.

Sundays were avoided for scheduling race activity dating all the way back to pre-500 races in 1909 and 1910. In early decades, Sundays were occasionally used for practice and/or qualifying, but were used sparingly in pre-World War II years. In some early years, practice may have been permitted on Sundays, but the gates might not be open to the public. When Tony Hulman bought the Speedway after World War II, Speedway management continued to refuse to schedule the race on a Sunday, a policy that stayed in place through 1973. Qualifying and practice, however, were regularly held on Sundays during those years, with no days closed to spectators.

Armed Forces Day also falls during the month of May, and usually coincides with one of the weekends of time trials. Since 1978 at the Speedway, that weekend is often filled with activities honoring the U.S. military, including an oath of enlistment ceremony.

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Wikipedia