While there is many a show that we love to simply skip past the opening credits of, Game of Thrones is not one of them (well unless we are watching about fifteen episodes in a row). One of the main reasons is because they are constantly adapting it, adding in and removing locations to the creative graphics as they go.

We used to think there was some kind of method to it all, in that you were viewing locations that were going to be shown in each episode, but that hasn't turned out to be true. We had started to notice that some locations are just consistently always shown, whether they are in an episode or not.

So what's the reasoning behind what we see in each episode's opening credits and what we don't? Well Game of Thrones producer Greg Spence has solved this mystery once and for all.

Spence explained that the main point of the opening credits was to get across the vast expansive world of the Seven Kingdoms, he told Hitfix; "The way the main title, and the way that the camera travels, and crossing the Narrow Sea into Essos is important to us," says Spence, "because it communicates the expanse of the show, and it helps to remind the audience of the entire world in which the show takes place. I think if we tried to limit the main title to just places that appear in the episodes, or we're literally tracing each character, it would be more confusing and less successful at its primary task, which is really orienting people to the world."

He went on to explain why some places are always shown, like King's Landing, Winterfell, the Wall and wherever Daenerys is at the moment, as these are the seats of the primary group of powers in the show.

Overall though, it seems they choose what locations to show based on an overall season, rather than one particular episode; "For continuity we would imagine that the title sequence and the path it travels is more representative of the season than a literal translation," says Spence.

It would also be extremely time-consuming and expensive to adjust it for every episode, with Spence saying; "It would be untenable, both from a production point of view, and probably from a cost point of view, to make a completely customized 3D animated, 90 second sequence before every single episode. That would be a tremendous financial and creative burden. What you do see is a very complicated 3D build. The guys at Elastic begin working in October in order to deliver the sequences to us in February and March. So it's quite a bit of manpower and man hours that goes into it."

There are usually "three or four camera paths per season", says Spence, "and within those paths, there's a certain amount of revisited towns and cities, and we reuse animation, and we balance that with new camera moves and new animation."

So finally, we know! Long story short - the opening credits are by season, and not by episode. And there's about three or four variations used every season.

Here, have a gander at the intro from the first season once more and appreciate the sheer awesomeness of it all...

Watch: Preview of next week's Game of Thrones...