A detection of a boundary in an environment. For this purpose, information of an occupancy grid is used, wherein the occupancy grid provides information about the probability of occupancy in the environment. Upon detecting a starting transition point between a free and an occupied grid cell in the occupancy grid, a region of interest window surrounding the starting transition point is analyzed to identify further transition points. The identified transition points are combined to one or more polygon chain. After the analysis of the boundary is performed within the region of interest, successive regions of interest may be analyzed. For this purpose, the successive regions of interest are determined based on the transition points and/or the boundary information of a current region of interest window.