Navigation apparatus and a navigation method

Obtaining information about the departing point of departure point, route travel at the set vehicle deviates from the route (S101) at the point of departure; after departing from the related travel history of the vehicle after a deviation from the deviation route acquired at the point of departure with historical information, the vehicle is deviated from the set route travel and the vehicle (S109) at a point offset from off-route; based departing from the travel history information for each vehicle to determine whether the deviation deviates from the vehicle along the set route at after departing from the point of departure route travel is changed (S110); and if it is judged that the vehicle is determined to deviate from traveling along a route change rate is a first predetermined value or more (S111: yES); a guide at a point deviated from the route is determined inappropriate ( S112). Thus, the guide can be appropriately determined at the point of departure route is appropriate.