The settlements we have on the map are the most important settlements for the provinces they inhabit and stone walls were a common site for these big cities. Understand that most seiges did not end in assaults by the main army and instead the defending army was either relieved by an assisting force or they were starved into submission. Assaulting stone walls was not meant to be anything less than a slaughter for the attacking force. However I do agree with you with the Epic Stone Walls, they just feel too skyscraper-ish.

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