There is a Mitarashi Festival at Shimogamo shrine.
You can foot bath in the cold refreshing water of Mitarashi pound and get yourself purifiied:)
This is the only time in the whole year you could get in it:)
It's melting hot now in Kyoto, so why don't you cool yourself down there:)?
This is a blog from last year about the festival.
All in Japanese but you can get the idea still.