Navigation apparatus

In a navigation apparatus, when a first detour route for detouring part of an initial route is present and calculation of a second detour route is instructed, a route search processing unit (28) determines whether the ratio of the distance of the first detour route to the total distance to be traveled when a vehicle returns to the initial route from the current position thereof via the first detour route and travels to a destination exceeds a preset value. If the ratio does not exceed the preset value, the route search processing unit (28) increases cost of at least a link associated with the first detour route, and searches for the second detour route. If the ratio exceeds the preset value, the route search processing unit (28) searches for a new route that links the current position of the vehicle and the destination.