1. A navigation apparatus for guiding a mobile system along a predetermined path comprising means to detect a path movement of the mobile system, memory means to store three-dimensional predictive patterns relating to positional information of the mobile system, vision means to observe an actual environment and to detect an actual image thereof, image processing means to extract an observed feature pattern from the observed image obtained with said vision means, and guidance control means to compare the observed feature pattern from said image processing means and the predicted pattern delivered from said memory means in accordance with the positional information of the mobile system and to provide a guidance signal for the mobile system as an output.