Although the capacity to navigate by environmental boundaries has been widely documented, the perceptual and physical factors that define a boundary have yet to be defined. In this study, we tested children’s navigation in spatial arrays consisting of 20 freestanding objects with varied inter-object spacing and length. Children begin to successfully compute locations using aligned (but discontinuous) object arrays around the seventh year of age. Our results suggest a late-emerging capacity of extrapolating geometric information from discontinuous structures.