Hi Sam, ferries get class 3 for routing, which is high. They should be easily used in routing when allowed in GPS. If the problem really is low routing class of service roads, then I see 2 solutions: Convince OSM mappers to add more tags for "highway=service". This could be for example "service=ferry". Or add any other indication, that these roads carry important traffic, for example include roads in a relation. Then this could be processed by mkgmap. Second solution would be to try to catch the problem by mkgmap. I think there are more similar cases, where 2 important roads are connected by a link or roundabout with significantly lower routing class. Mkgmap could include following algorithm: Find all suspicious objects, like highway links, roundabouts, service roads connected to a ferry and analyze other roads connected to this object. If any of these other roads get road_class 3 or 4, then increase road_class of processed object accordingly to 3 or 4. -- Best regards, Andrzej