Board Thread:Manga/@comment-3568954-20150810140746/@comment-5774380-20150810161123

In fact, they have ballons. If you remember, Djel Sanes confessed that he murdered a couple that attempted to travel outside the Walls in a hot air ballon. That was precisely the problem: the government was always secretly sabotaging the attempts of people to leave the Walls and learn of the outside world and the truth about the Titans; but now that the old government has been taken down then there is no reason, and that's indeed a possibility that has not been explored and a potential plot hole. Congratulations, you have just ruined the Return to Shiganshina arc. xD