Syr Darya played a special role in the life of Otrar and the whole region, and its waters were used for irrigation. They were also known for being abundant with fish and its shores were covered with rich vegetation and were also home to many birds and animals. Otrar is mentioned in numerous sources such as medieval Arab, Persian and Turkic authors. These sources refer to it as one of the Zhetysu (Seven Rivers) towns. The town was situated at the junction of different geographical landscapes and was at the intersection of the caravan ways of the Great Silk Road. Otrar, being at the junction of the two great rivers, was the center of the large agricultural region and, being near the foothills of the Karatau mountains, became one of the supporting fortresses of the nomads wandering in the steppes. From Otrar, along the Arys, roads spread out to Taraz, Balasagun and further on to Chinese Xinjiang; along the Syr Darya an old road went up to Shash, Sogd and then to Merv and Nishapur, and another road went down to Pre-Aral and Ural. Another well known road ran through Kzylkum moving westward to Khorezm and on to the Volga region, the Black Sea and the Caucasus.