So while wanking on some of the Foundation parallels mentioned in the last thread, I kind of stumbled onto something interesting regarding the Celmomian Prophecy and the idea that Ishuäl is the Second Foundation. You might not want to read this if you haven't read the Foundation series though.
According to the Prophecy, an Anasûrimbor will return at the "end of the world." So far the assumption is that this refers to the time period when the Consult will bring about the end of the world in the Second Apocalypse. There is a similar line in the Foundation series concerning the location of the Second Foundation. It is not given but we are told that it's at "the other end of the galaxy." That can be translated to "the other end of the world" in Eärwa. Which is very similar to Celmomas's "end of the world."
So the trick to this particular crackpot is to think of the "end of the world" in terms of location
and not time. To someone from the Mandate - in the south-east of Eärwa, it actually seems that the Demua Mountains, where Ishuäl is located, is quite literally at the end of the world - the north-west of Eärwa. (Beyond it are only the Consult and the Nonmen.) However, Celmomas himself was on the Fields of Eleneöt when he made the prophecy, which is in the north-west and very near Ishuäl to begin with. So the end of the world as predicted by Celmomas is really "at the other end of the world" (from Ishuäl) - the south-east of Eärwa, which is near where the Mandate is but not the actual place. The same is true with the Foundation series where "the other end of the galaxy" turns out to be a trick and the actual location is somewhere else.
So where is it? Before he died, Seswatha built two towers, Atyersus, where the Mandate is based, and Attrempus, where ... not a lot has happened really. I've always wondered why Seswatha would waste his time building Attrempus for no apparent reason when he had a Second Apocalypse to worry about, especially since the Mandate is not even using it directly. According to the Glossary, the word Attrempus means "Tower of Respite." I know what the word respite means but more important is how Bakker uses the word in the series. If the name is supposed to give us some hint then he must have used in some unique way. From the epigraph of chapter 14 of TDTCB:
"What are the works of men if not a momentary respite, a hiding place soon to be discovered..."
"A momentary respite, a hiding place..." Respite: a hiding place... A hiding place.
That can't be a coincidence. Seswatha must have built the tower to conceal something, most likely a ruined Nonman Mansion beneath it where something or someone is hiding.