A contour maps contains contour strains which might be imaginary traces connecting points of equivalent elevation. Such strains are drawn on the plan of an area soon after setting up reduced amounts of numerous factors in the area. This is how you understand Official Sites use .gov A .gov website https://contour-survey-in-dhaka02311.blog-a-story.com/12831967/detailed-notes-on-contour-survey-in-bangladesh