Tower of the Hand
From A Wiki of Ice and Fire
The tower's small hall is a long room with a high-vaulted ceiling and bench space for two hundred. The private audience chamber is not as large as the king's, but has Myrish rugs, wall hangings, and a golden-tinted round window that give it a sense of intimacy.
The Secret Passageway
There is a secret passageway to the tower know to Varys. In the tower there is a bedchamber with a canopied bed and sconces on the walls and rushes on the floor. This is the Hand's bedchamber. From inside the hearth of this bedchamber there is a small secret door. From this door one can climb down 230 rungs which lead to a small round a chamber where half a dozen tunnels meet.
A Game of Thrones
Eddard Stark is appointed Hand and moves into the Tower of the Hand.
A Clash of Kings
A Storm of Swords
Lord Tywin takes over as Hand and moves into the Tower of the Hand.
Before fleeing the Red Keep, Tyrion visits his father in the tower, gaining access through the secret passageway. There, in the Hand's bedchamber, he discovers his whore Shae in Tywin's bed. He strangles her, arms himself with a crossbow and then confronts his father in the privy and slays him in fury and escapes the same way he came in.
A Feast for Crows
Lord Tywin is discovered murdered in the Tower of the Hand. As Cersei is about to view her father's body which has been moved to his bed, she notices the secret door that she was told about when the news of Tywin's death was delivered. The door gapes open behind the ashes of the hearth, no bigger than an oven. She thinks to herself that a man would need to crawl through it.
Jaime Lannister and his men reduce the Tower of the Hand to a shell looking for Tyrion. Cersei decides to burn the tower. When Jaime asks her if she means to burn the tower she tells him that she will after Tommen’s wedding feast. Cersei tells Jaime that their father was murdered in the Tower of the Hand and she cannot bear to look at it.
After Tommen and Margaery Tyrell’s wedding feast Cersei leads the guests outside to watch as the pyromancers set the Tower of the Hand on fire. Fifty pots of wildfire placed inside the tower along with logs and casks of pitch are set alight. The Tower of the Hand is a ruined. The greater part of Tyrion Lannister’s possessions, which were still in the tower, were also destroyed.
Later, outside of Riverrun, Genna Lannister asks Jaime if it is true that Cersei burned the Red Keep but Jaime tells her that it was only the Tower of the Hand. Genna replies that Cersei would have done better to leave the tower and burn her Hand
A Dance with Dragons
Cersei tells Kevan Lannister that Tommen told her than Mace Tyrell intends on rebuilding the Tower of the Hand. Kevan concurs telling her that the new tower is to be twice as tall as the one she burned.