Backyard
A backyard can be more or less hidden, and more or less untidy; perhaps trash has been left behind in the area, and maintenance has fallen behind in favor of the front. In such cases, the backyard likely represents inferiority, hidden aspects of ourselves, things that can’t quite stand the light of day, the inferior function in Jung’s typology, and so on. (In other words, a similar symbolic value to "under the bed.")
A beautiful backyard—for such places also exist in both dreams and reality—naturally carries a more positive symbolic value, but is still more or less concealed. (Compare with Back Door.)