The distance between two successive contours indicate the slope of the land.

Contours are the lines, drawn on the map, which join the places that have same height above the mean sea level. The contours are marked with a number, known as contour value, which shows the height of the land in metres. Thus the difference between two successive contours (contour interval) depicts the difference in heights of two points on land. Thus, contour interval being same, widely spaced contours will depict a gentle slope while closely-spaced contours will depict a steep slope.