People mover (2) comprising an endless tread belt (6) formed from several tread elements (4) connected to one another, which is driven by a drive unit about a first and second reversal point (22), and a side skirt (24) moved along with tread belt (6), the side skirt (24) comprising flange elements (28) joined to the tread element (4) and bridge elements (30) connected movably relative to flange elements (28). A sensor (38) is arranged adjacent to the side skirt (24), the sensor (38) having a limited detection range perpendicular to the circulation direction of side skirt (24), and a plurality of marking elements are arranged in a line on side skirt (24) along the circulating direction having a limited width perpendicular to the circulating direction.