The Eyrie is the ancient seat of House Arryn, one of the oldest lines of Andal nobility. It is situated high on the mountain known as the Giant’s Lance, and is reachable only by a narrow mule trail, guarded by the Gates of the Moon and three small waycastles; Stone, Snow and Sky. The Eyrie is the smallest of the great castles, consisting only of a cluster of slim towers. It is supplied by means of a massive dumbwaiter that extends down to the topmost waycastle. While many, including Lysa Arryn, claim that the Eyrie is impregnable due to it mountainous surroundings, this advantage is not permanent, as winter snows can make supplying the fortress impossible. The Eyrie’s dungeons, known as “sky cells,” are particularly infamous; they are left open to the cold sky, and many prisoners commit suicide rather than remain imprisoned. Executions in the Eyrie are carried out via the Moon Door, which opens from the high hall onto a sickening six hundred foot drop to the stones of the mountain. The Eyrie is also unique in that it lacks a godswood; no weirwood tree would take root in the stony soil.
The Eyrie was held by Lord Jon Arryn, who fostered Ned Stark and Robert Baratheon prior to the War of the Usurper. Lord Arryn was the first to raise his banners in rebellion against House Targaryen. After the war Lord Arryn served as King Robert I Baratheon’s King’s Hand. After Lord Arryn was assassinated, his wife Lysa Arryn took her sickly child, Robert, and fled once more to the Eyrie. Lysa refused to align herself with any of the claimants during the War of the Five Kings, but eventually consented to an alliance with House Lannister after Petyr Baelish agreed to marry her. Baelish killed Lysa after she attempted to execute Sansa Stark (who was disguised as Baelish’s bastard daughter), and now rules in the Eyrie as the Lord Protector and Regent for the sickly, stunted Lord Robert Arryn.