A navigation system includes an image search unit for searching across an
image database by using image data transmitted from an image data input
unit, as a search key, a search-result output unit for displaying at
least one piece of image data extracted by the search on a display, and a
destination determination unit for reading point information
corresponding to image data selected by a user from the display and
determining the read point information to be a destination. Where
information about the location, name, telephone number, zip code,
address, and so forth, of a point which the user wants to determine to be
the destination is not provided, the point can be searched by using image
data including an image of the building or scenery of the point.