NAVIGATION DEVICE

The present invention enables to move an enlarged map displayed as a slave screen within a large-area map screen freely and at high speed. A navigation device includes: a map display means for displaying a large-area map screen showing a large-area map and displaying an enlarged map screen showing a partial enlarged map obtained by enlarging a partial region of the large-area map in superposition on the large-area map screen at a display position of the partial region; a speed calculation means for calculating a speed pertaining to movement of the enlarged map screen; an enlarged map creation means for creating an enlarged map obtained by enlarging a predetermined region including the partial region of the large-area map based on vector data of a detailed map obtained by enlarging the large-area map; and a selection means for selecting the partial region of the large-area map as the partial enlarged map when the speed pertaining to the movement is no lower than a reference speed and selecting a region of the enlarged map, corresponding to the partial region, as the partial enlarged map when the speed pertaining to the movement is lower than the reference speed.