Dragonstone had been the westernmost outpost of Valyrian power for two centuries. Its location athwart the Gullet gave its lords a stranglehold on Blackwater Bay, and enabled both the Targaryens and their close allies, the Velaryons of Driftmark (a lesser house of Valyrian descent), to fill their coffers off the passing trade. Velaryon ships, along with those of another allied Valyrian house, the Celtigars of Claw Isle, dominated the middle reaches of the narrow sea, whilst the Targaryens ruled the skies with their dragons.
Thus armed he went forth from Turgon’s hall, and stood upon the high terraces of Taras in the red light of the sun. None were there to see him, as he gazed westward, gleaming in silver and gold, and he knew not that in that hour he appeared as one of the Mighty of the West, and fit to be the father of the kings of the Kings of Men beyond the Sea, as it was indeed his doom to be; but in the taking of those arms a change came over Tuor son of Huor, and his heart grew great within him.
Many have claimed that the Eyrie of the Arryns is the most beautiful castle in all the Seven Kingdoms, and it is hard to deny the truth of this (…). Seven slim white towers crown the Eyrie where it sits high upon a shoulder of the Giant’s Lance, and no castle in Westeros boasts more marble in its walls or upon its floors. And yet the Arryns and the men of the Vale will tell you that the Eyrie is impregnable as well, for its position high atop the mountainside makes it all but impossible to assault.
“And out of the west there would come at times a great cloud in the evening, shaped as it were an eagle, with pinions spread to the north and the south; and slowly it would loom up, blotting out the sunset, and then uttermost night would fall upon Númenor. And some of the eagles bore lightning beneath their wings, and thunder echoed between sea and cloud.
Then men grew afraid. ‘Behold the Eagles of the Lords of the West!’ they cried. ‘The Eagles of Manwë are come upon Númenor!’ And they fell upon their faces.” -The Silmarillion
Casterly Rock, the ancient seat of House Lannister, is no ordinary castle . Although crowned with towers and turrets and watchtowers, with stone walls and oaken gates and iron portcullises guarding its every means of egress, this ancient fortress is in truth a colossal rock beside the Sunset Sea, a rock that some say looks like a lion in repose when the sun sets and the shadows fall.
“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… 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.” - The Return of the King
Paintings by Alan Lee, John Howe, and Ted Nasmith. German Diagram by Unknown (let me know if you find the artist so I can give credit)