Mental maps have been widely used to explore the interplay between physical and social geographies. As Tim Ingold (2000) has argued, asking respondents to represent in a piece of paper their everyday spatial incursions may be very telling, not as a way to claim that the drawings are actual maps people have in their minds (and use for navigation), but mostly as the representations that they are.

I argue in this paper that the way migrants living in Lisbon represent distances, pathways, and landmarks may tell us something about the way they relate to the city and become familiarized with its spaces. Mental maps let see grey zones, interstitial space that only comes up as one makes the effort to draw a coherent map-like image.

Migrants' mental maps expose some of the ways urban space was rationalized, coded and (re)arranged, and allow us to see their active roles in producing, testing and manipulating urban practical knowledge. I analyse their urban savoir-faire as it shapes their spatial integration in Lisbon and discuss some of the potentialities and limitations of the mental maps in migration research.