dead island If you travel to prison, you won't be able to go back Make sure you're ready to leave the island before you continue?

Answer 1

this takes you to the final part of the game, though theres still a bunch of sidequests you can do there

it just means once you go to the prison you cant get back so those side wuests before the prison can not be done, jin goes with you so you still get your storage :)