Arrajan (Argan) was a medieval Persian city located between Fars and Khuzestan, which was settled since Elam period and an important in the Sasanian period until the 11th century. It was the capital of a medieval province of the same name, which corresponds to the modern-day Behbahan of Khuzestan Province, Iran. The archaeological site of Arrajan covers an area of about 3.75 km2 (1.45 sq mi), with only scattered traces of buildings, walls, a castle, a qanat, a dam, and a bridge across the nearby Marun river.