And there where the White Mountains of Ered Nimrais came to their end he saw, as Gandalf had promised, the dark mass of Mount Mindolluin, the deep purple shadows of its high glens, and its tall face whitening in the rising day. And upon its out-thrust knee was the Guarded City, with its seven walls of stone so strong and old that it seemed to have been not builded but carven by giants out of the bones of the earth.
Even as Pippin gazed in wonder the walls passed from looming grey to white, blushing faintly in the dawn; and suddenly the sun climbed over the eastern shadow and sent forth a shaft that smote the face of the City. Then Pippin cried aloud, for the Tower of Ecthelion, standing high within the topmost walls shone out against the sky, glimmering like a spike of pearl and silver, tall and fair and shapely, and its pinnacle glittered as if it were wrought of crystals; and white banners broke and fluttered from the battlements in the morning breeze and high and far he heard a clear ringing as of silver trumpets.
So Gandalf and Peregrin rode to the Great Gate of the Men of Gondor at the rising of the sun, and its iron doors rolled back before them.
...
For the fashion of Minas Tirith was such that it was built on seven levels, each delved into the hill, and about each was set a wall, and in each wall was a gate. But the gates were not set in a line: the Great Gate in the City Wall was at the east point of the circuit, but the next faced half south, and the third half north, and so to and fro upwards; so that the paved way that climbed towards the Citadel turned first this way and then that across the face of the hill. And each time that it passed the line of the Great Gate it went through an arched tunnel, piercing a vast pier of rock whose huge out-thrust bulk divided in two all the circles of the City save the first. For partly in the primeval shaping of the hill, partly by the mighty craft and labour of old, there stood up from the rear of the wide court behind the Gate a towering bastion of stone, its edge sharp as a ship-keel facing east. Up it rose, even to the level of the topmost circle, and there was crowned by a battlement; so that those in the Citadel might, like mariners in a mountainous ship, look from its peak sheer down upon the Gate seven hundred feet below. The entrance to the Citadel also looked eastward, but was delved in the heart of the rock; thence a long lamp-lit slope ran up to the seventh gate. Thus men reached at last the High Court, and the Place of the Fountain before the feet of the White Tower: tall and shapely, fifty fathoms from its base to the pinnacle, where the banner of the Stewards floated a thousand feet above the plain.
A strong citadel it was indeed, and not to be taken by a host of enemies, if there were any within that could hold weapons; unless some foe could come behind and scale the lower skirts of Mindolluin, and so come upon the narrow shoulder that joined the Hill of Guard to the mountain mass. But that shoulder, which rose to the height of the fifth wall, was hedged with great ramparts right up to the precipice that overhung its western end; and in that space stood the houses and domed tombs of bygone kings and lords, for ever silent between the mountain and the tower.
Pippin gazed in growing wonder at the great stone city, vaster and more splendid than anything that he had dreamed of; greater and stronger than Isengard, and far more beautiful.
...
And then he found himself at the doors of the great hall beneath the gleaming tower; and behind the wizard he passed the tall silent door-wardens and entered the cool echoing shadows of the house of stone.
They walked down a paved passage, long and empty,..
...
Gandalf halted before a tall door of polished metal.
...
He knocked on the door.
The door opened, but no one could be seen to open it. Pippin looked into a great hall. It was lit by deep windows in the wide aisles at either side, beyond the rows of tall pillars that upheld the roof. Monoliths of black marble, they rose to great capitals carved in many strange figures of beasts and leaves; and far above in shadow the wide vaulting gleamed with dull gold, inset with flowing traceries of many colours. No hangings nor storied webs, nor any things of woven stuff or of wood, were to be seen in that long solemn hall; but between the pillars there stood a silent company of tall images graven in cold stone.
Suddenly Pippin was reminded of the hewn rocks of Argonath, and awe fell on him, as he looked down that avenue of kings long dead. At the far end upon a dais of many steps was set a high throne under a canopy of marble shaped like a crowned helm; behind it was carved upon the wall and set with gems an image of a tree in flower.

(LoTR, V-1)

For the main wall of the City was of great height and marvellous thickness, built ere the power and craft of Númenor waned in exile; and its outward face was like to the Tower of Orthanc, hard and dark and smooth, unconquerable by steel or fire, unbreakable except by some convulsion that would rend the very earth on which it stood.
...
...
It was against the Gate that he would throw his heaviest weight. Very strong it might be, wrought of steel and iron, and guarded with towers and bastions of indomitable stone, yet it was the key, the weakest point in all that high and impenetrable wall.

(LoTR, V-4)

The chief city of this southern realm was Osgiliath, through the midst of which the Great River flowed; and the Númenóreans built there a great bridge, upon which there were towers and houses of stone wonderful to behold, and tall ships came up out of the sea to the quays of the city.
Other strong places they built also upon either hand: Minas Ithil, the Tower of the Rising Moon, eastward upon a shoulder of the Mountains of Shadow as a threat to Mordor; and to the westward Minas Anor, the Tower of the Setting Sun, at the feet of Mount Mindolluin, as a shield against the wild men of the dales. In Minas Ithil was the house of Isildur, and in Minas Anor the house of Anárion, but they shared the realm between them and their thrones were set side by side in the Great Hall of Osgiliath.
...
Then Osgiliath, which in the waning of the people had long been deserted, became a place of ruins and a city of ghosts. But Minas Anor endured, and it was named anew Minas Tirith, the Tower of Guard; for there the kings caused to be built in the citadel a white tower, very tall and fair, and its eye was upon many lands.
Proud still and strong was that city, and in it the White Tree still flowered for a while before the house of the Kings; and there the remnant of the Númenóreans still defended the passage of the River against the terrors of Minas Morgul and against all the enemies of the West, Orcs and monsters and evil Men; and thus the lands behind them, west of Anduin, were protected from war and destruction.

(Silm, OF THE RINGS OF POWER AND THE THIRD AGE)

Minas Anor - 'Tower of the Sun' (also simply Anor), afterwards called Minas Tirith; the city of Anárion, at the feet of Mount Mindolluin. 361-2, 365-8, 377

Minas Tirith (2) - Later name of Minas Anor. 297. Called the City of Gondor. 377

minas - 'tower' in Annúminas, Minas Anor, Minas Tirith, etc. The same stem. occurs in other words referring to isolated, prominent, things, e.g. Mindolluin, Mindon; probably related is Quenya minya 'first' (cf. Tar-Minyatur, the name of Elros as first King of Númenor).

tir - 'watch, watch over' in Minas Tirith, palantíri, Tar-Palantir, Tirion.

(Silm, Appendix)