There are three big festivals (or matsuri) in Kyoto: Gion, Jidai and Aoi. I never saw the Aoi matsuri when I lived here because after seeing the Gion and Jidai ones I learned that it was all the same thing over and over again and so not worth the crowds. However as we were here and the Aoi matsuri was on, it felt like a waste not to attend.
The crowds were terrible though.
tariq.ca 