We automatically calculate routes for all trips trough Mapzen trough GraphHopper and OpenStreetMap.
Route calculation is done based on trip types, to make for instance a bicycle trip optimized for bicycles. Routes are calculated in the order the caches have in the trip, there is no route optimizing here.
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The map data used as the basis for Mapzenfor GraphHopper's route calculation engine comes from OpenStreetMap.
The quality varies from place to place, but in many places it's very good.
What's important to know is that if you think it's bad quality, you can help contribute to make it better!
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