A sixth-century mosaic preserved in the so-called Hippolytus Hall at Madaba in Jordan depicts what appear to be three urban tychai labelled 'Rome', 'Gregoria', and 'Medaba' above a large panel depicting some mythological scenes of a sexual nature. The present note argues that the tychai labelled 'Rome' and 'Gregoria' personify virtues, ‘strength’ and ‘vigilance’, which the artist wished to associate with Madaba, and not towns of these names. As a group, these tychai served to provide an explicit moral justification for the depiction of the associated mythological scenes.