A curvimetre measuring instrument is simple to use. All you need to do is roll the wheel along the route that you want to calculate. The instrument’s display glass will show the accumulated distance. But before you begin, make sure that you set the counter to zero. This is very obvious, but sometimes we forget and get inappropriate results. Also, the results you will get will either display real-world distances or the actual distance on the map. You can differentiate between the two by looking at the units.