A rich historiography exists on the subject of port towns, yet too often they are treated not on their own terms, but as the terminal point either of maritime space or of the terrestrial realm. This chapter outlines a new approach, drawing on vocabulary from the marine and littoral sciences and from the discipline of island studies to articulate an approach that is truly focussed on the coastal zone. It is necessary to adapt some of this vocabulary to suit the needs of urban history. The foreshore corresponds to the relatively small area that welcomes strangers and processes cargo, passengers, or tourists. The offshore is a space of idiosyncratic governance, both excised from the port town and yet often an integral part of its operations. Scholars interested in ethnic, gender, and civic identities are working on a deeper, more complex mixture that might well be called the urban estuary.