a robotic work tool comprising at least one sensor unit configured to collect sensed input data, wherein the at least one sensor unit is configured to collect the sensed input data while the robotic work tool is driven at least a portion of a lap around the working area to preliminarily define a perimeter around the working area;

at least one controller configured to establish a preliminary working area perimeter; and

at least one memory configured to store a perimeter adjustment function and further including instructions that, when executed by the at least one controller, cause the at least one controller to adjust the perimeter of the working area by applying the perimeter adjustment function to the preliminary working area perimeter and thereby produce an adjusted working area perimeter, wherein the perimeter adjustment function is based on the collected sensed input data and wherein the sensed input data corresponds to terrain features;

wherein adjusting the perimeter of the working area comprises:

detecting one or more edges in the working area, wherein the one or more edges correspond to terrain feature edges; and

applying the perimeter adjustment function to the preliminary working area perimeter to align the adjusted working area perimeter to be substantially parallel with and spaced apart from the one or more edges.