CHARACTERISTICS OF CONTOURS: The principal characteristics of contour lines which help in plotting or reading a contour map are as follows: I. The horizontal distance between any two contour lines indicates the amount of slope and varies inversely on the amount of slope. II. Widely spaced contour represent the flat surface. III. Closely spaced contour represent steep slope ground. IV. Equally spaced contour represent uniform slope. V. Irregular contours indicate uneven surface. VI. Concentric closed contours with decreasing values towards centre indicate a pond. VII.Concentric closed contours with increasing values towards centre indicate hills. VIII.Contour lines with U-shape with convexity towards lower ground indicate ridge. IX. Contour lines with V-shaped with convexity towards higher ground indicate valley. X. Contour lines generally do not meet or intersect each other except in overhanging cliff. XI. Contours do not pass through permanent structures such as buildings. XII.A contour line must close itself but need not be necessarily within the limits of the map.