The Keep on Chapterhouse was the central hub all of Sisterhood activity during the Return of the Honored Matres and the advent of Kralizec. After The Scattering, the Bene Gesserit's decided to continue to make Chapterhouse their permanent base of operations. The central located building on Chapterhouse housed the nerve center of the organization -- The Keep. A series of one to four story buildings, the sprawling complex blended in, and became one with the natural flora and fauna that surrounded it.