Prisons are mostly absent from modern imaginaries of the medieval urban panorama. The oversight is remarkable given the volume of studies on medieval criminality and social marginality, on the one hand, and the close link between the foundation of prisons and the explosion of late-medieval civic architecture, on the other. The main problematic of late-medieval urban prisons stemmed from their role in traditional Christian imaginaries. By then, prisons had become essential cogs in the machinery of justice throughout and beyond Italy. The breadth of netherworldly allusions in da Nono's vision offers a unique vantage point for examining other descriptions of medieval urban prisons, which tended to limit themselves to one 'department' of the afterlife. True, prison descriptions were few and far between – a fact partially responsible for modern scholars' ignorance about the degree to which prisons were part of the late-medieval urban experience.