you know after they meet at the sophia spot then start driving till they run out of gas? did they mention where they were going?
heading to the coast is actually not a bad idea. The zombies have one less direction to come at you from. If they could find a large barge or even an island, clear it of zombies, and live there it would be pretty safe. Though a prison works too. As long as you were sure all the actual inmates were gone.