Unfold your map and lay it out flat on a table or level surface. With the map unfolded, locate your starting point and your destination. Some maps have an index that will help you locate each point on the map.
Cut a piece of string approximately 12 inches long. Lay one end of the string on your starting point on the map. Use a piece of transparent tape to hold it in place. Stretch the string across the route until you reach your destination point. Cut off the extra length of string. String is particularly helpful when your route is not perfectly straight from point A to point B.
Lift the string off of the map and lay it on your ruler. Take note of how many inches long your string is.
Locate the bar graph at the bottom of your map. Typically 1 inch equals 100 miles. If your string is 5 inches long, your travel distance will be 500 miles.
