Gothregor is surrounded by massive outer walls. These walls are divided into sections by the gates. The stretch from the North Gate to the East Gate is known as the Ghost Walks. They hold apartments for the Knorth Highborn. As the Knorth numbers dwindled, they withdrew into the drum tower in the corner. At the time of the Knorth Massacre, all the Knorth women lived in that tower. The Moon Garden is built onto the wall of the Ghost Walks.
Boarding the Forecourt on the other side is the old Knorth keep. It's at the very heart of Gothregor, and built on the ruins of an ancient Merikit hill fort, even older than the Hathiri fortress which most of Gothregor was built on. Between the two front towers of the old keep is a swinging catwalk. The old keep houses the most important rooms of Gothregor: the death banner hall, a judgement hall, the High Council chamber, and the Highlord's personal study.
The keep had the same general outline as the larger fortress—rectangular with a drum tower at each corner. Its first floor was windowless and dark. Here the lord of Knorth dispensed domestic justice under flaring torches and the stern death banners of his family. The second floor—brighter, more richly appointed—also was a hall of judgment, but for disputes between other houses. The third floor, as usual, took Torisen's breath away as he stepped out of the spiral stair in the corner. All four walls between their stone arches were stained glass. Here the High Council met, under the emblems of all nine major houses blazing with light, three by three by three. On the fourth wall facing east was a map of Rathillien in colored glass,
– Torisen's narration, Dark of the Moon, "Chapter 6: The High Council"
↑Seeker's Mask, "Part I", II — "It would be dark there now, in those apartments built for the Highlord's family in Gothregor's massive outer wall—dark and cold and silent. The Ghost Walks, people called them, and kept their distance."
↑Seeker's Mask, "Part I", III — "Once the Knorth had occupied these mural apartments from the northern gate to the eastern, but they had been a dwindling house long before the massacre. On that spring night, the northeast drum tower had been large enough to house them all."
↑To Ride a Rathorn, "Chapter VIII: A Forgotten Name", I — "Outside lay the broad inner ward of the Knorth fortress, with the garrison's barracks in the outer wall to the right. To the left rose the Old Keep."
↑ 4.04.14.2Honor's Paradox, "Chapter VIII: New Year's Eve", II — "Around the ward were his garrison's domestic offices and lodgings; across it, the old keep; beyond that, the Women's Halls, and then an acre of desolation—all within the walls of the greater fortress."
↑ 5.05.1Seeker's Mask, "Part I", I — "The windows looked down on the Forecourt, so called because it occupied the foremost open space in the Women's Halls, which themselves occupied the back half of Gothregor. At the center of the entire fortress was the old Knorth keep, whose own rear half projected into the Forecourt. A horse was clattering in through the gate which separated the court from the fortress's inner ward."
↑Seeker's Mask, "Part II: Gothregor", VI — "Here was the Forecourt and across it, the old Knorth keep. Actually, the keep's lowest level long preceded the Kencyrath's tenure in this valley, or even that of the Hathiri. The ruins of ancient Merikit hill forts lined the Silver, many of them, as here, worked into the foundations of later buildings."
↑Dark of the Moon, "Chapter 6: The High Council" — "he opened the southern door and stepped out of the tower. Beyond was a narrow platform, then a catwalk suspended between the keep's two front towers. […] The walk swayed back and forth, twenty feet down to the flat roof of the keep, seventy to the flagstones before the door."