This paper describes a Navigation System for private automobiles. This system shows the accurate position of the vehicle on a CRT map display and also displays useful information such as the locations of hotels, golf clubs, etc. A sophisticated map matching method is employed to find the vehicle's position. In this method, a set of correlation coefficients between the locus and the mapped roads is used to determine the vehicle's location statistically. A unique automatic calibration function is also added to the magnetic field sensor to compensate for malfunctioning and detection errors caused by distortion due to the earth's magnetism and to magnetization of the vehicle at points of high field density such as railroad crossings. In this system, we can see the current position of the vehicle indicated by a pointer on the smooth scrolling map display. This digital map has scales of 1/25.000, 1/100,000. and 1/400,000 and covers all of Japan with two available display modes: "north up" and "heading up". This system also shows the direction and distance to This whatever destination the user has chosen. This navigation system has been installed in Nissan's 1989 Cedric/Gloria and Cima models.