House Lannister Targaryen is the ruling house of Westeros. It was formed in 505AC when King Damon Lannister and Queen Danae Targaryen agreed to divide power equally after the War of the False King. Its sigil is the banner of House Lannister alongside the banner of House Targaryen though it is often depicted as a lion and dragon back-to-back, tails entwined.
Seat: The Red Keep
The Red Keep is a castle and the home of the kings of the Seven Kingdoms. It located in King's Landing, the capital of the Seven Kingdoms, where it sits on Aegon's Hill. Aegon the Conqueror first set foot on Westeros in the area of King's Landing at the start of his War of Conquest. On the highest of the three hills of the area, named Aegon's Hill, he built his first fort of earth and wood, the Aegonfort. After the completion of the Conquest, Aegon ordered the construction of a permanent royal castle on the hill. The construction was completed during the reign of Maegor I Targaryen, who killed all those who worked on the castle to preserve its secrets.
The Red Keep is made of pale red stone. It has seven massive drum-towers crowned with iron ramparts. Massive curtain walls surround the keep, with nests and crenelations for archers. Thick stone parapets, some four feet high, protect the outer edge of the wall ramparts, where the heads of traitors are traditionally placed on iron spikes between the crenels at the gatehouse. The walls have great bronze gates and portcullises, with narrow postern doors nearby. The immense barbican has a cobbled square in front of it. Behind the walls are small inner yards, vaulted halls, covered bridges, barracks of the gold cloaks, dungeons and granaries.
Inside, the Keep holds the Iron Throne, the seat of the monarch, and has several gathering halls, including the Great Hall and the Queen's Ballroom. Relics of the Targaryen dynasty, such as dusty suits of black armor and dragons' skulls, sit in hallways. Doors are made of oak banded with black iron. Rushes are used on the floors as the weather cools. Overall, the Keep is not particularly large, being smaller than Winterfell.
Daena Lannister Targaryen was born.
"The marriage was a poor idea. A Targaryen and a Lannister mix like oil and water. They are both too proud, too vain, too conceited to share power. Lannisters think they are the gods' gift to mankind, and Targaryens think they are gods themselves." - Sarella Martell