A navigation system having a travel situation detection function for providing a navigation route of a travel between a start point and an end point includes a storage unit and an inference engine. The storage unit stores a travel purpose determiner that suitably determines a travel purpose according to a travel situation of a predetermined type having time specificity, and the inference engine infers the end point of the travel based on the travel purpose that results from an application of a detected travel situation by the travel situation detection function to the travel purpose determiner.
