As with most maps, the distance between two points on a Colorado state highway map can be calculated using a standard ruler. Most maps contain a scale that indicates a representative fraction of distance. Measuring the distance between points and using basic math results in a rough distance between points.
Map scales are often displayed as a fraction such as 1/100,000 or 1:100,000. After measuring the distance with a ruler, multiply this number by the denominator for the actual distance. Sometimes the scale indicates that an inch or other unit of measurement is equal to a particular distance instead of a fraction.