Emergency First Aid Kit
Despite whatever the festival is providing, never leave home without a small stash of emergency first aid. True story: I got food poisoning at Bonnaroo, it was 95 degrees outside and there were only porta potties. It was not good. I sure wish I had remembered to bring some medicine to ease that situation. Now every year we keep some upset-stomach meds in the car along with some Advil, some Band-Aids and other medicine cabinet staples just in case.