Game of Thrones Season 7 Episode 5 is here. At to start with, the show considered those different châteaux to exist, as we found in Season 3, when Bran and organization keep running into Sam and Gilly at the Nightfort, the principal army to be worked in the Wall, where the Lord Commander was once positioned. (It was additionally the primary Castle to be relinquished as the numbers and spending plan to keep up the Wall dwindled.)
Yet, via Season 4, they'd changed their tune, with just the three above showing up on the guide, of which just Castle Black is kept an eye on.
The western most purpose of the Wall in the show is the keep known as the Shadow Tower, which is referenced a great deal in the books, yet never observed. It is essentially where the Wall keeps running into the mountain go known as the Frostfangs, that keeps running along the edge of the Lands of Always Winter. (In the books, there is a keep more remote toward the west, Westwatch-by-the-Bridge, however it is relinquished.)