The township of Behbahan in Khuzestan Province has a semi-desert like climate, with hot scorching summers and rainy winters. Its center is Behbahan city, which is located at a distance of 1,105 km. from Tehran. The ruling center of ancient times was known as "Qobad Foreh" and "Arkan". Qobad Ebne Firooz was the first person responsible for constructing "Arrehjan" (Behbahan) city.
During the Sassanian era, the city of Arrehjan which is located at a distance of 12 km. from the current city of Behbahan, was erected. After the destruction of Arrehjan city, the inhabitants flocked to Behbahan. In the 4th century BC the city of Arrehjan was fully populated, but in the second half of the 8th century, not a trace of Arrehjan remained, and in a short period the current city of Behbahan replaced the former.