Casterly Rock is carved out of a great stone hill colossal rock beside the Sunset Sea. The Rock has been measured at three times the height of the Wall or the Hightower of Oldtown. It is almost two leagues long from west to east, and contains tunnels, dungeons, storerooms, barracks, halls, stables, stairways, courtyards, balconies, and gardens. In the bowels of the Rock are rooms where caged lions were once kept, and cells for the worst prisoners. The Lion's Mouth, the main entry to Casterly Rock, is an enormous natural cavern reaching two hundred feet high. Its steps are now wide enough for twenty riders. Its port has docks, wharves, and shipyards and is accessible by longships and cogs.