Chapter 109

King’s Landing used the Red Keep atop the high hill as its inner city, while the high walls built later formed its outer defenses, creating a city-defense layout that commanded the ground from above.

It had seven gates, and the Mud Gate was the target Domeric had chosen to attack, because it was the closest one to the Red Keep.

Once the Mud Gate was taken, his spearhead could directly threaten Cersei, the Kingslayer Jaime, and the rest of their party inside the Red Keep.