Here's my post from last year....educate yourselves and then start dousing each other!
We were up early and we were all soaked by 9am. Nothing like being woken up with a big cup of water in your face.
You are angry at first...
...and then you retaliate.
(we also went to the live webcam I mentioned here and waited to see it happen in public in Krakow but Martin says he thinks it's been outlawed downtown because complete strangers were getting soaked by school children... you should still check it out...it's beautiful day there today, although a bit cold to be covered in water)