"Deep is the abyss that spanned by Durin’s Bridge, none has measured it," said Gimli.

"Yet it has a bottom, beyond light and knowledge," said Gandalf. "Thither I came at last, to the uttermost foundations of stone. He was with me still. His fire was quenched, but now he was a thing of slime, stronger than a strangling snake. We fought far under the living earth, where time is not counted. Ever he clutched me, and ever I hewed him, till at last he fled into dark tunnels. Far, far below the deepest delving of the Dwarves, the world is gnawed by nameless things. Even Sauron knows them not. They are older than he. Now I have walked there, but I will bring no report to darken the light of day. In that despair my enemy was my only hope, and I pursued him, clutching at his heel. Thus he brought me back at last to the secret ways of Khazad-dum: to well he knew them all. Ever up now we went, until we came to the Endless Stairs. From the lowest dungeon to the highest peak it climbed, ascending in unbroken spiral in many thousands steps, until it issued at last in Durin’s Tower carved in the living rock of Zirak-zigil, the pinnacle of the Silvertine.”