Shaded relief map of the United States. This map shows the elevation of the 48 contiguous states. The "3-D" effect is produced by illumination from the left side of the image. Land surfaces that slope toward the light source are bright; surfaces that slope away from the light source are dark. Areas with high relief show the immediate juxtaposition of very dark shades and very light shades. Areas with low relief show little contrast between medium gray shades. The closeup map below highlights four topographic features found in and adjacent to NJ. CP=Coastal Plain; Pd=Appalachian Piedmont; VR=Appalachian Valley & Ridge; AP=Appalachian Plateau. From the USGS website Tapestry of Time and Terrain.