Contemporary cities are physical and virtual. This thesis describes the findings of a mixed-methods study concerning visual images of the city in the urban Northeast of the United States. I ground these approaches in existing literature concerning digital media, visual narrative, genre ecology, urban planning, and virtual places. The first part of the study analyzes the results of a survey in which 150 people responded to questions about social media use and the relationships between image type and the functions of social media in urban contexts. The second part of the study analyzes the results of coding one year of visual images tweeted by @CambMA, the municipal Twitter feed for the City of Cambridge, Massachusetts. These approaches required the development of new tools for analyzing visual communication and genre moves in specific media contexts. My research suggests that specific image types are suited for specific media functions in the context of visual communication in virtual urban environments and that some image types are especially effective in capturing and expressing the city. These findings provide potential strategies for municipal social media channels to consider in terms of how they communicate with their audiences.