In the period 5500-4500 BC north Mesopotamia shared a common culture, called Halaf after the site where the evidence was first found. Many small agricultural villages have been found with distinctive buildings known as tholoi, round domed structures with or without antechambers. They were made of different materials depending on what was available locally: limestone boulders or tauf (an Arabic word for a type of building material made with mud and straw).
The Halaf culture is also characterized by a distinctive type of pottery, found from south-east Turkey across to Iran, but which may have its origins in the region of the River Khabur (modern Syria). Halaf pottery was extremely well made and beautifully decorated which probably explains why it spread so far. The best Halaf sites include Arpachiyah, Sabi Abyad and Yarim Tepe. The Halaf culture was eventually absorbed into the so-called Ubaid culture, with changes in pottery and building styles.