Method for cleaning sand, in particular for cleaning sand on sandpits, playgrounds and sports facilities, by means of a mobile sand cleaning apparatus having a frame which can move on the sand surface and on which a sand elevator can be adjusted, in particular lowered and raised, which elevator is equipped with an endless, circulating conveyor device provided with a large number of conveyor elements that circulate between a digging position in which they are inserted into the sand to be cleaned and a dumping position from which the sand transported in the conveyor elements is thrown onto a sieve located on the sand cleaning apparatus, which sieve allows the sand to pass through and separates out impurities, which enter a collection container, the frame standing or moving on the original surface of the sand layer to be cleaned; the adjustment/lowering of the sand elevator relative to the frame causing the lower edge of the lowermost conveyor element to be inserted to varying degrees of depth into the sand layer below the sand surface (digging depth) on which the frame stands or moves; and the adjustment/lowering being detected by means of a sensor, preferably a laser distance sensor, which generates corresponding electrical signals that are transmitted to a signal processing device located on the sand cleaning apparatus, which signal processing device receives these signals, processes these signals into data, and stores, keeps and/or provides the data thus obtained for further internal or external processing in order to use these data to calculate and display the sand volume circulated by the sand cleaning apparatus in a given period of time; characterised in that, at the same time, position signals relating to the position of the sand cleaning apparatus in the region to be cleaned are generated and transmitted to the signal processing device by means of a receiver for satellite position data attached to the sand cleaning apparatus, and the position signals are linked to the electrical signals of the sensor by the signal processing apparatus in such a way that the digging depth is plotted on a two-dimensional map of the position data and different colours are assigned to the digging depth values, so that a coloured 2-dimensional map which shows the sand depth at each position is generated from the position data and the assigned measured digging depth values, or a 3-dimensional image of the sand surface which shows the sand depth at each position is generated by means of the digging depth values and the position data. in particular for cleaning sand on sandpits, playgrounds and sports facilities, by means of a mobile sand cleaning apparatus having a frame which can move on the sand surface and on which a sand elevator can be adjusted, in particular lowered and raised, which elevator is equipped with an endless, circulating conveyor device provided with a large number of conveyor elements that circulate between a digging position in which they are inserted into the sand to be cleaned and a dumping position from which the sand transported in the conveyor elements is thrown onto a sieve located on the sand cleaning apparatus, which sieve allows the sand to pass through and separates out impurities, which enter a collection container, the frame standing or moving on the original surface of the sand layer to be cleaned; the adjustment/lowering of the sand elevator relative to the frame causing the lower edge of the lowermost conveyor element to be inserted to varying degrees of depth into the sand layer below the sand surface (digging depth) on which the frame stands or moves; and the adjustment/lowering being detected by means of a sensor, preferably a laser distance sensor, which generates corresponding electrical signals that are transmitted to a signal processing device located on the sand cleaning apparatus, which signal processing device receives these signals, processes these signals into data, and stores, keeps and/or provides the data thus obtained for further internal or external processing in order to use these data to calculate and display the sand volume circulated by the sand cleaning apparatus in a given period of time; characterised in that, at the same time, position signals relating to the position of the sand cleaning apparatus in the region to be cleaned are generated and transmitted to the signal processing device by means of a receiver for satellite position data attached to the sand cleaning apparatus, and the position signals are linked to the electrical signals of the sensor by the signal processing apparatus in such a way that the digging depth is plotted on a two-dimensional map of the position data and different colours are assigned to the digging depth values, so that a coloured 2-dimensional map which shows the sand depth at each position is generated from the position data and the assigned measured digging depth values, or a 3-dimensional image of the sand surface which shows the sand depth at each position is generated by means of the digging depth values and the position data.