Method for determining the spatial extent of a free queue, proceeding from position information, comprising the following steps: a) subdividing a monitoring region comprising the free queue into a plurality of positions; b) proceeding from the position information, identifying objects assigned to the free queue; c) tracking the identified objects; d) periodically storing a current position of at least a portion of the tracked objects; e) determining an average speed of at least a portion of the objects, wherein the average speed of an object is determined on the basis of a plurality of the stored positions of the respective object; characterized in that the method comprises further the following steps: f) creating a first map, which records, in relation to the positions in the monitoring region, an appearance density of objects at the corresponding positions, objects having an average speed outside a predefined range not being taken into account when creating the first map, wherein the first map is an assignment between area or spatial regions and the presence probabilities of objects situated there; g) proceeding from a predefined exit region of the free queue, carrying out a flood fill method for generating a continuous region corresponding to the extent of the free queue, wherein proceeding from a field in the first map, the respectively adjacent fields are tested to establish whether they have a certain appearance density h) wherein "free queue" refers to a queue whose members are situated in a substantially continuous zone and whose end position is known, but not the position of the beginning of the queue and the shape of the queue within a genuinely two-dimensional zone. a) subdividing a monitoring region comprising the free queue into a plurality of positions; b) proceeding from the position information, identifying objects assigned to the free queue; c) tracking the identified objects; d) periodically storing a current position of at least a portion of the tracked objects; e) determining an average speed of at least a portion of the objects, wherein the average speed of an object is determined on the basis of a plurality of the stored positions of the respective object; f) creating a first map, which records, in relation to the positions in the monitoring region, an appearance density of objects at the corresponding positions, objects having an average speed outside a predefined range not being taken into account when creating the first map, wherein the first map is an assignment between area or spatial regions and the presence probabilities of objects situated there; g) proceeding from a predefined exit region of the free queue, carrying out a flood fill method for generating a continuous region corresponding to the extent of the free queue, wherein proceeding from a field in the first map, the respectively adjacent fields are tested to establish whether they have a certain appearance density h) wherein "free queue" refers to a queue whose members are situated in a substantially continuous zone and whose end position is known, but not the position of the beginning of the queue and the shape of the queue within a genuinely two-dimensional zone.