# ArcGIS Cost Path Analysis. How to extract the area covered by the many possible shortest paths?

As you can see in the picture ArcGIS Cost Path Analysis produces different results based on chosen direction (blue path direction: start->stop, red path direction: stop->start). As Cost Path Analysis only works in 8 directions, there are many possible shortest paths in the example above. Some of the shortest paths are located in between the blue and the red path. This got me thinking:

Do you see a possibility to extract the area covered by the many possible shortest paths?

There are large areas of identical costs in this example. Light colors represent low costs, dark colors reperesent high ones.

• It's a great question. What does the shading in the map represent--different impedances? – whuber Jan 25 '16 at 22:45

## 1 Answer

The solution is so simple. All you need is a Cost Distance Raster from the start point as well as from the stop point. Just use the Raster Calculator to add these two together and you will get a raster where the value of each cell representing the length of the shortest Cost Path it belongs to. So it is also possible to derive the area of self-defined maximal Path Costs. Path Cost stands in this case for the length of the Cost Path (impedances*path length).

Here you can see the resulting raster according to the map in the question (dark values - high Path Cost, light values - low Path Cost: Here I extracted the lowest value of the resulting raster to derive the area covered by the many possible shortest paths (red area): EDIT: You can use the Corridor function to produce this raster. Well, it has been thought of. :-)