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In this short article we'll describe why it does not make sense to calculate alternative routes with more than two waypoints.
 
If you calculate a route with two waypoints the result consist of exactly 1 leg, which is in this simple case the complete route.
 
With more than 2 waypoints you have more than 1 leg, for instance 3 waypoints will give you 2 legs.
 
To get an alternative route for every leg would technically be not a big deal but the problem comes afterwards.
 
How do you want to combine the alternative routes from every leg?
 
This is a combinatorial problem to return alternative routes for the whole route as the amount of possible combination rises pretty quickly. 

Another downside to this is that calculating alternative routes takes a lot longer than using regular routing for each leg.
 
Furthermore in case of calculating alternative routes per leg, there is the risk to run into time-outs.

If you want to use more than two waypoints we recommend to split the route and create a request for every leg and calculate the alternative route from these results.
 
 
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