No electrics and no freezer for ice blocks! any suggestions?

[lisad123]

Going wild camping with my sister hopefully this summer.
I have checked the site and there is no freezer for ice blocks. Im wondering how we will manage for a week? Any suggestions? Is there a type of cool box you can run off a car battery?

My dad run his battery out last year using cool box in the car!
Will do the ice in bag and sale trick and freeze as much of the food as possible before we go. Thanks
We are only 20 mons from my house so can keep half food there in freezer and run back half way though the week