You can bring it in any way you choose, as long as (as others have said) it is not in a glass bottle. I always pack water bottles and some bottles of gatorade as well just in case we want something else to drink. We usually stay in a hotel with a fridge so I ice them the night before that way they stay really cold while your touring the parks and we can drink them whenever we want. DH and I always carry a bookbag so I use that and pack some snacks as well- granola bars, small bags of chips, etc. It helps to tide us over while waiting in lines