Aleppo is one of the oldest continuously inhabited cities in the world; it may have been inhabited since the sixth millennium BC. Excavations at Tell as-Sawda and Tell al-Ansari, just south of the old city of Aleppo, show that the area was occupied by Amorites by the latter part of the third millennium BC. That is also the time at which Aleppo is first mentioned in cuneiform tablets unearthed in Ebla and Mesopotamia, which speak of it as part of the Amorite state of Yamhad, and note its commercial and military importance. Such a long history is attributed to its strategic location as a trading center between the Mediterranean Sea and Mesopotamia.