Transition in house plans from the circular to the rectangle in Neolithic in the Upper Mesopotamia.

   Architecture is one of the distinctive features of Upper Mesopotamia, in which many forms of house design emerged which identified by the human need and the quality of the raw materials available within its environment. In this area, older homes were appeared, and what could be the beginning of the house was made in whole of the ancient Near East. This architecture consisted of primitive forms in its design and technique of construction, mostly, they consisting of a circular chamber with a small opening representing the entrance.  With the advent of the Neolithic period within the ninth millennium BC, Architecture evolved somewhat from its predecessors, although it maintained its circular or oval plan, and residential house at this period became more spacious and organized, and was divided from the inside. Then, in the mid of this period, a great architectural development took place, with the transition to straight construction, Rectangular and square houses appeared at existing angles.