 Over the course of the next week and a half, two-thirds of the Eternal City was left in ashes. This was the stuff of nightmares. As Tacitus described, the blaze and its fury ran first through the level portions of the city, then rising to the hills while it again devastated every place below them. It outstripped all preventative measures. So rapid was the mischief and so completely at its mercy the city, with those narrow, winding passages and irregular streets which characterized Old Rome."