Picking up his staff he stood before the rock and said in a clear voice: Mellon!
The star shone out briefly and faded again. Then silently a great doorway was outlined, though not a crack or joint had been visible before. Slowly it divided in the middle and swung outwards inch by inch, until both doors lay back against the wall. Through the opening a shadowy stair could be seen climbing steeply up;
...
The wide stairway was sound and undamaged. Two hundred steps they counted, broad and shallow; and at the top they found an arched passage with a level floor leading on into the dark.

The passage (behind the stair at the west gate) twisted round a few turns, and then began to descend. It went steadily down for a long while before it became level once again. The air grew hot and stifling, but it was not foul, and at times they felt currents of cooler air upon their faces, issuing from halfguessed openings in the walls. There were many of these. In the pale ray of the wizard's staff, Frodo caught glimpses of stairs and arches and of other passages and tunnels, sloping up, or running steeply down, or opening blankly dark on either side. It was bewildering beyond hope of remembering.
...
Often the wizard consulted him (Gimli) at points where the choice of way was doubtful;
...
There were not only many roads to choose from, there were also in many places holes and pitfalls, and dark wells beside the path in which their passing feet echoed. There were fissures and chasms in the walls and floor, and every now and then a crack would open right before their feet. The widest was more than seven feet across, and it was long before Pippin could summon enough courage to leap over the dreadful gap. The noise of churning water came up from far below, as if some great mill-wheel was turning in the depths. 'Rope!' muttered Sam. 'I knew I'd want it, if I hadn't got it!' As these dangers became more frequent their march became slower. Already they seemed to have been tramping on, on, endlessly to the mountains' roots.

They had been going for several hours with only brief halts, when Gandalf came to his first serious check. Before him stood a wide dark arch opening into three passages: all led in the same general direction, eastwards; but the left-hand passage plunged down, while the right-hand climbed up, and the middle way seemed to run on, smooth and level but very narrow.
...
To the left of the great arch they found a stone door: it was half closed, but swung back easily to a gentle thrust. Beyond there seemed to lie a wide chamber cut in the rock.
...
He (Gandalf) went in cautiously, and the others filed behind. 'There!' he said, pointing with his staff to the middle of the floor. Before his feet they saw a large round hole like the mouth of a well. Broken and rusty chains lay at the edge and trailed down into the black pit. Fragments of stone lay near.
...
'This seems to have been a guardroom, made for the watching of the three passages,' said Gimli. 'That hole was plainly a well for the guards' use, covered with a stone lid. But the lid is broken, and we must all take care in the dark.'
...
he (Pippin) crept to the edge and peered over. A chill air seemed to strike his face, rising from invisible depths. Moved by a sudden impulse he groped for a loose stone, and let it drop. He felt his heart beat many times before there was any sound. Then far below, as if the stone had fallen into deep water in some cavernous place, there came a plunk, very distant, but magnified and repeated in the hollow shaft.

I (Gandalf) shall take the right-hand passage. It is time we began to climb up again.' For eight dark hours, not counting two brief halts, they marched on; and they met no danger, and heard nothing, and saw nothing but the faint gleam of the wizard's light, bobbing like a will-o'-thewisp in front of them. The passage they had chosen wound steadily upwards. As far as they could judge it went in great mounting curves, and as it rose it grew loftier and wider. There were now no openings to other galleries or tunnels on either side, and the floor was level and sound, without pits or cracks. Evidently they had struck what once had been an important road; and they went forward quicker than they had done on their first march.

when suddenly the walls to right and left vanished. They seemed to have passed through some arched doorway into a black and empty space. There was a great draught of warmer air behind them, and before them the darkness was cold on their faces. They halted and crowded anxiously together. Gandalf seemed pleased. 'I chose the right way,' he said. 'At last we are coming to the habitable parts, and I guess that we are not far now from the eastern side. But we are high up, a good deal higher than the Dimrill Gate, unless I am mistaken. From the feeling of the air we must be in a wide hall.
...
He raised his staff, and for a brief instant there was blaze like a flash of lightning. Great shadows sprang up and fled, and for a second they saw a vast roof far above their heads upheld by many mighty pillars hewn of stone. Before them and on either side stretched a huge empty hall; its black walls, polished and smooth as glass, flashed and glittered. Three other entrances they saw, dark black arches: one straight before them eastwards, and one on either side.
...
(Gandalf said) 'There used to be great windows on the mountain-side, and shafts leading out to the light in the upper reaches of the Mines. I think we have reached them now, but it is night outside again, and we cannot tell until morning.

He woke and found that the others were speaking softly near him, and that a dim light was falling on his face. High up above the eastern archway through a shaft near the roof came a long pale gleam; and across the hall through the northern arch light also glimmered faint and distantly.
...
'Maybe,' said Gandalf. 'But I do not know yet exactly where we are. Unless I am quite astray, I guess that we are above and to the north of the Great Gates; and it may not be easy to find the right road down to them. The eastern arch will probably prove to be the way that we must take; but before we make up our minds we ought to look about us. Let us go towards that light in the north door. If we could find a window it would help, but I fear that the light comes only down deep shafts.'
Following his lead the Company passed under the northern arch. They found themselves in a wide corridor. As they went along it the glimmer grew stronger, and they saw that it came through a doorway on their right. It was high and flattopped, and the stone door was still upon its hinges, standing half open. Beyond it was a large square chamber. It was dimly lit, but to their eyes, after so long a time in the dark, it seemed dazzlingly bright,
...
upon the floor, and stumbled among things lying in the doorway whose shapes they could not at first make out. The chamber was lit by a wide shaft high in the further eastern wall; it slanted upwards and, far above, a small square patch of blue sky could be seen. The light of the shaft fell directly on a table in the middle of the room: a single oblong block, about two feet high, upon which was laid a great slab of white stone. 'It looks like a tomb,' muttered Frodo, and bent forwards with a curious sense of foreboding, to look more closely at it. Gandalf came quickly to his side. On the slab runes were deeply graven:
'BALIN SON OF FUNDIN LORD OF MORIA.'
...
There was another smaller door on the other side of the chamber, under the shaft. By both the doors they could now see that many bones were lying, and among them were broken swords and axe-heads, and cloven shields and helms. Some of the swords were crooked: orc-scimitars with blackened blades. There were many recesses cut in the rock of the walls, and in them were large iron-bound chests of wood. All had been broken and plundered; but beside the shattered lid of one there lay the remains of a book.

'Back to the hall,' answered Gandalf. 'But our visit to this room has not been in vain. I now know where we are. This must be, as Gimli says, the Chamber of Mazarbul; and the hall must be the twenty-first of the North-end. Therefore we should leave by the eastern arch of the hall, and bear right and south, and go downwards. The Twenty-first Hall should be on the Seventh Level, that is six above the level of the Gates.

Off you go, all of you, down the stairs! Wait a few minutes for me at the bottom, but if I do not come soon, go on! Go quickly and choose paths leading right and downwards.'
'We cannot leave you to hold the door alone!' said Aragorn.

Gandalf took no turns, right or left, for the passage seemed to be going in the direction that he desired (bending southwards). Every now and again it descended a flight of steps, fifty or more, to a lower level.
...
At the end of an hour they had gone a mile, or maybe a little more, and had descended many flights of stairs. There was still no sound of pursuit. Almost they began to hope that they would escape. At the bottom of the seventh flight Gandalf halted. 'It is getting hot!' he gasped. 'We ought to be down at least to the level of the Gates now. Soon I think we should look for a left-hand turn to take us east.
...
They could now see their way (because of the fire in the 2nd hall): in front the road sloped down swiftly, and some way ahead there stood a low archway; through it the glowing light came. The air became very hot.
...
(Gandalf said) we have reached the First Deep, the level immediately below the Gates. This is the Second Hall of Old Moria; and the Gates are near: away beyond the eastern end, on the left, not more than a quarter of a mile. Across the Bridge, up a broad stair, along a wide road through the First Hall, and out! But come and look!' They peered out. Before them was another cavernous hall. It was loftier and far longer than the one in which they had slept. They were near its eastern end; westward it ran away into darkness. Down the centre stalked a double line of towering pillars. They were carved like boles of mighty trees whose boughs upheld the roof with a branching tracery of stone. Their stems were smooth and black, but a red glow was darkly mirrored in their sides. Right across the floor, close to the feet of two huge pillars a great fissure had opened. Out of it a fierce red light came, and now and again flames licked at the brink and curled about the bases of the columns.
...
'If we had come by the main road down from the upper halls, we should have been trapped here,' said Gandalf. 'Let us hope that the fire now lies between us and pursuit.

Suddenly Frodo saw before him a black chasm. At the end of the hall the floor vanished and fell to an unknown depth. The outer door could only be reached by a slender bridge of stone, without kerb or rail, that spanned the chasm with one curving spring of fifty feet. It was an ancient defence of the Dwarves against any enemy that might capture the First Hall and the outer passages. They could only pass across it in single file.
...
'Lead the way, Gimli!' he (Gandalf) said. 'Pippin and Merry next. Straight on and up the stair beyond the door!'
...
At the top (of the stair) was a wide echoing passage.
...
They ran on. The light grew before them; great shafts pierced the roof. They ran swifter. They passed into a hall, bright with daylight from its high windows in the east. They fled across it. Through its huge broken doors they passed, and suddenly before them the Great Gates opened, an arch of blazing light