Even if you’re a super fan, we bet you’ll be caught off guard by these surprising behind the scenes facts about Game of Thrones. From alternative casting choices, to production details, to fun facts about the actors, the set of this HBO series is full of fascinating trivia. Today, we’re going to find out what goes on behind The Wall. WatchMojo ranks the most surprising behind the scenes Game of Thrones fact. What do you think is the most surprising Game of Thrones behind the scenes fact? Let us know in the comments!