A positioning apparatus (12, 12A, 12B) comprising: a first calculator arranged to calculate a first position and a first attitude of a moving body indicating a relative position and a relative attitude of the moving body with respect to a reference position and a reference attitude, based on a plurality of images captured by an image capturing apparatus mounted on the moving body; wherein the positioning apparatus (12, 12A, 12B) further comprises: a storage apparatus arranged to store information on identifiers, positions, and attitudes of a plurality of markers disposed at predetermined positions and visually distinguishable from each other, and information on a map containing a passageway for the moving body; a second calculator arranged to extract one of the plurality of markers from an image captured by the image capturing apparatus, and calculate a second position and a second attitude of the moving body indicating a position and an attitude of the moving body in the map, based on a position and an attitude of the one extracted marker; and a corrector (36, 36A) arranged to correct the first position based on the second position to generate a third position of the moving body, wherein the corrector (36, 36A) is arranged to determine whether or not the moving body is turning, and when the moving body is turning, the corrector (36, 36A) is arranged not to correct the first attitude based on the second attitude, and generate the first attitude as a third attitude, and when the moving body is not turning, the corrector (36, 36A) is arranged to correct the first attitude based on the second attitude to generate a third attitude of the moving body. a first calculator arranged to calculate a first position and a first attitude of a moving body indicating a relative position and a relative attitude of the moving body with respect to a reference position and a reference attitude, based on a plurality of images captured by an image capturing apparatus mounted on the moving body; wherein the positioning apparatus (12, 12A, 12B) further comprises: a storage apparatus arranged to store information on identifiers, positions, and attitudes of a plurality of markers disposed at predetermined positions and visually distinguishable from each other, and information on a map containing a passageway for the moving body; a second calculator arranged to extract one of the plurality of markers from an image captured by the image capturing apparatus, and calculate a second position and a second attitude of the moving body indicating a position and an attitude of the moving body in the map, based on a position and an attitude of the one extracted marker; and a corrector (36, 36A) arranged to correct the first position based on the second position to generate a third position of the moving body, wherein the corrector (36, 36A) is arranged to determine whether or not the moving body is turning, and when the moving body is turning, the corrector (36, 36A) is arranged not to correct the first attitude based on the second attitude, and generate the first attitude as a third attitude, and when the moving body is not turning, the corrector (36, 36A) is arranged to correct the first attitude based on the second attitude to generate a third attitude of the moving body. a storage apparatus arranged to store information on identifiers, positions, and attitudes of a plurality of markers disposed at predetermined positions and visually distinguishable from each other, and information on a map containing a passageway for the moving body; a second calculator arranged to extract one of the plurality of markers from an image captured by the image capturing apparatus, and calculate a second position and a second attitude of the moving body indicating a position and an attitude of the moving body in the map, based on a position and an attitude of the one extracted marker; and a corrector (36, 36A) arranged to correct the first position based on the second position to generate a third position of the moving body, wherein the corrector (36, 36A) is arranged to determine whether or not the moving body is turning, and when the moving body is turning, the corrector (36, 36A) is arranged not to correct the first attitude based on the second attitude, and generate the first attitude as a third attitude, and when the moving body is not turning, the corrector (36, 36A) is arranged to correct the first attitude based on the second attitude to generate a third attitude of the moving body.