User blog comment:Omega natsu2/Fairy Tail Zero: A Moonlit Lake, Review./@comment-24536822-20141117171523/@comment-7418318-20141117173216

That ruined building is Cardia Cathedral. Apart from them outright saying it, just look at those stained glass windows (I hope that's the right term). The guild hall doesn't have those or two towers left and right of the main entrance.