Illurambar (or the Walls of the World) borded the entierty of Arda. Upon it were the Gates of Morning and the Door of Night.
Now jump to the Fall of Numenor and we have the bending of the world. Its safe to assume that a lot of things changed. Ekkia probably turned into what we now know as the atmosphere and Illurambar was destroyed, no?
Well thats what I get from various maps of Arda and sources from the web.
Now, if the Door of Night stood on this Wall. How come other sources talk of the Wall of Night? The Wall of Night is where the Door of Night now stands after the bending of Arda and it borders Ea and the Void. Is that right?
The whole point of this thread is to explain Dagor Dagorath. I'm not sure if Tolkien made it official or not but its there.
Dagor Dagorath (or the final battle) is supposed to happen WAY in the future.
"Thus spake Mandos in prophecy, when the Gods sat in judgement in Valinor and the rumour of his word was whispered among all the Elves of the West. When the world is old and the Powers grow weary, then Morgoth, seeing that the guard sleepeth, shall come back through the Door of the Night out of the Timeless Void; and he shall destroy the Sun and the Moon. But Eärendil shall descend upon him as a white and searing flame and drive him from the airs. Then shall the Last Battle be gathered on the fields of Valinor. In that day, Tulkas shall strive with Morgoth, and on his right hand shall be Eonwe, and on his left Túrin Turambar, son of Húrin, coming from the halls of Mandos; and the black sword of Túrin shall deal unto Morgoth his death and final end; and so shall the Children of Húrin and all Men be avenged. Thereafter shall Earth be broken and remade, and the Silmarils shall be recovered out of Air and Earth and Sea; for Eärendil shall descend and surrender that flame which he hath had in keeping. Then Fëanor shall take the Three Jewels and bear them to Yavanna Palúrien; and she will break them and with their fire rekindle the Two Trees, and a great light shall come forth. And the mountains of Valinor shall be levelled, so that the light shall go out over all the world. In that light the Gods will grow young again, and the Elves awake and all their dead arise, and the purpose of Ilúvatar be fulfilled concerning them. But of Men in that day the prophecy of Mandos doth not speak, and no Man it names, save Túrin only, and to him a place is given among the sons of the Valar."
In other texts, Mr.Tolkein says that Elves have no part in it and it will be Men etc etc... but we know how he loves to change things, but lets ignore that now.
This is my thesis: Illurambar was part of Arda before it was bent. During that time The Gates of Morning and the Door of Night stood on the Uttermost east and west of Arda. After it was bent, the Doors of Night and the Gates of Morning were moved onto the Wall of Night which now bordered Ea and the Void. Years late Morgoth breaks the Doors of Night and comes into Ea once more.
It's a confusing concept for me anyway, and I hope I haven't confused you.