Keeping cans cool.

Going to a festival this weekend. I don't really drink spirits so that more or less forces me to bring beer in cans with me. Seeing as I'll be going Thursday-Monday do you have any tips for keeping it cool?

And what would you say would be the drink that would taste least rotten warm?

Cider is okay warm more so than beer anyway.

I never bothered fighting it at all the festivals I have been to. Just keep it in some shade under a gazebo and put it just inside your tent when your not there so it dont get stolen. Sometimes I have used cool box with a few ice packs which keeps it semi cool. Anther idea could be take a bucket of water and fill it with water from the water point when you are gonna have a few cans and chill them in the cold water (its always really cold no matter what festival) then empty when you are raedy to move out and watch some bands.