Map reading is a cognitively demanding spatio-geometric activity for children that involveunderstanding and updating person-space-map relations during movement in a large environment. Drawing from the psychological literature, children’s skills in reasoning about those relations were tested in two tasks of a map-based treasure hunt on the campus ( self-location and place finding), and compared them to their performances in a set of spatial tasks in paper and pencil format. 9- to 12-year old children (N=240) placed colored stickers and arrows on the map to describe their location and orientation at three different places, and laid down three disks to mark locations they identified. Hierarchical linear regression analysis revealed that performances in a set of written spatial tasks predicted up to one quarter of the variance in performances in both map-reading tasks, while sex and strategy choice were not found to be important predictors.