1. A map generation method comprising: obtaining successive images that are successively taken while a moving body is moving; extracting a local feature quantity at each feature point from the successive images obtained in the successive image acquisition step; performing matching among the local feature quantities in the successive input images, the local feature quantity being extracted in the local feature quantity extraction step; calculating an average of matched local feature quantities among a predetermined number of successive images in the feature quantity matching step as an invariant feature quantity; calculating distance information corresponding to each invariant feature quantity based on a position of the moving body at each point in time when the successive images are obtained; and generating a local metrical map as a hybrid map including the invariant feature quantity and the distance information.