1. A method of providing a map for display comprising: determining, by one or more computing devices, whether an image of a geographic location contains a feature having image characteristics consistent with image characteristics of a person's shadow, the image being associated with a time, and the image characteristics of a person's shadow being based at least in part on the time associated with the image; generating, by the one or more computing devices, visual indicia based at least in part on the determination of whether an image of a geographic location contains a feature having image characteristics consistent with the image characteristics of a person's shadow; generating, by one or more computing devices, a map of the geographic location and the visual indicia; and providing for display, by one or more computing devices, the map of the geographic location and the visual indicia.