Humans sort their landscape around them in mental maps. It is something we have done since the stoneage. Before maps compasses and GPS our ability to pinpoint places was a mater of life or death. A hunter uses large rocks or special threes, and remember where he and his mates killed the mammut acording to them. A medicineman uses the same rock and tree to remember wher the mushroom with the funny effect grew last year. Modern humans still sort their world in mental maps according to their "function" in society.