This article examines Mazara del Vallo as a border city. As port to the Mediterranean’s largest fishing fleet, the city figures in an ongoing dispute with neighbouring Tunisia over fishing rights. Accelerating European integration has redefined Sicily’s southern shore as a European border. And Tunisian immigrants now make up five percent of the city’s population. In the 1970s, union anger, political mobilisations, and popular antipathy all worked to stamp Tunisians as undesirable and unwelcome. By the late 1990s, the lot of Tunisians in Mazara had improved with stable employment and family formation. While integrated economically, Tunisians remain socially and symbolically excluded. The actions and orientations of Sicilians, Tunisians, and their respective states perpetuate these multiple divisions. This study shows how the movement of people can involve states and their respective populations in the creation of complex divisions and interactions, in ways which can activate borders. The remarkable volume of migration in contemporary Sicily, southern Europe, and beyond makes the study of borders timely and challenging.