A method for determining reference elements of an environment, the method comprising at least the steps of: providing a ceiling value and a floor value; measuring, using a distance-measuring sensor, a set of environment point positions, each position comprising at least a first coordinate along a first direction and a second coordinate along a second direction non collinear with the first direction; determining reference elements of the environment comprising position of the set of environment point positions whose second coordinate is strictly smaller than the ceiling value and strictly higher than the floor value, and whose distance to the distance-measuring sensor, taken along the first direction, is a highest distance in a set of distances of environment points to the distance-measuring sensor, said distances being taken along the first direction.