 Excavations conducted in 1931/2 at Tepe Giyan by Georges Contenau and Roman Ghirshman led to the conclusion that Nahavand and its environs have been inhabited since prehistoric times.It showed that the site of Tepe Giyan, which lies kilometers southeast of Nahavand, was occupied since at least 5,000 BC to BC.During the Achaemenid period (550–330 BC), Nahavand was located in the southernmost part of Media, on the fertile Nisaean plain.