Terrain information, like contour lines, hillshade, slope, help you to visually assess the lay of the land, the relief, navigability, and more. The topographic information can on the map be represented by contour lines, relief shading and/or steepness coloring.

The underlying data originates from SRTM and ASTER.

Further reading at %1$s.
Vergemoontlik dei aflaai van aflyn kontoerlyne en heuwelsakdus ('Instellings'-> 'Inligtingsbestuur' -> 'Aflaai' -> Kies verlangde kaart-tipe).