Image gallery Chapter 3: Getting started with GRASS Image Gallery for North Carolina (NC, USA) OSGeo Educational data set Download free OSGeo Educational data set! Fig. 3.5. Shaded elevation raster map with overlayed vector streams, major roads and overpasses (p. 31) Aspect map with overlayed major roads (p. 32) Elevation surface and landclass96 raster map with overlayed vector streams, lakes, and major roads shown in nviz