Labeling contours in AutoCAD Civil 3D is similar to labeling contours in Land Desktop. Actually, the process is similar but the end result is different. Basically you drape a Contour Label Line across multiple contours. This is the same as using Label Group Interior in Land Desktop. Everywhere a contour intersects the Contour Label Line, a contour label appears. The contour labels themselves remain on the Contour Label Line and not on the contour itself. If you drag the label line to different locations, the labels move with it. If you alter contour intervals, for example, and if the new contours intersect the label line, they are automatically labeled. This new contour behavior in AutoCAD Civil 3D may take some practice to get used to, but the time savings of being able to make minor to extensive changes to your surface without having to constantly re-label the contours is substantial. You access the contour labeling features either by clicking on a surface in the drawing, or by clicking Surfaces on the Modify tab. Either of these methods displays the Surfaces tab on the ribbon. On the Labels and Tables panel of the Surfaces tab, click the drop-down arrow next to Add Labels to display the list of contour labeling commands. Select Contour - Single, Contour - Multiple, or Contour - Multiple At Interval.
After selecting a contour labeling command, you are prompted to pick two points in model space. The line defined by these points becomes your Contour Label Line. Like everything else in AutoCAD Civil 3D, contour labels are controlled by styles. By modifying these styles, you can adjust the label look-and-feel to match your particular organization’s requirements.