1. A navigation device that has a navigation function and guides a travel path from a current position of the navigation device to a destination on a map image, the device comprising: a display that displays the map image; circuitry configured to: search for a point of interest existing around the current position on the map image; dynamically change a search subject area for searching for the point of interest by enlarging and reducing a search subject area setting frame on the display, the search subject area setting frame designating the search subject area, when a designation specified by a user is received by the navigation device; and automatically determine the search subject area setting frame based on a current traveling direction of the navigation device and whether an area on the map image is a vehicle stoppable area.