Nahavand () is a city in Hamadan Province, Iran. It is the capital of Nahavand County. At the time of the 2006 census, its population was 72,218, in 19,419 families. It is located south of the city of Hamadan, west of Malayer and northwest of Borujerd. Inhabited continuously since prehistoric times, Nahavand was bestowed upon the House of Karen in the Sasanian period. During the Muslim conquest of Persia, it was the site of the famous Battle of Nahavand. Name The name Nahāvand is probably ultimately derived from Old Persian *Niθāvanta-, related to the Old Persian name Nisāya, itself derived from the prefix ni-, meaning "down" and a second element which is related to Avestan si or say, meaning "to lie down". It has been spelled differently in different books and sources: Nahavand, Nahavend, Nahawand, Nahaavand, Nihavand, Nehavand, Nihavend, or Nehavend, formerly called Mah-Nahavand, and in antiquity Laodicea (; Arabic Ladhiqiyya), also transliterated Laodiceia and Laodikeia, Laodicea in Media, Laodicea in Persis, Antiochia in Persis, Antiochia of Chosroes (), Antiochia in Media (), Nemavand and Niphaunda. Geography Nahavand is situated in the west of Iran, in the northern part of the Zagros region. It lies kilometers south of Hamadan, from which it is separated by the massif of the Alvand subrange. This massif grants Nahavand and its hinterlands an abundant water supply. Historically, Nahavand was located on a route that led from central Iraq through Kermanshah to northern Iran, and was therefore often crossed by armies. Another historic road, coming from Kermanshah, leads towards Isfahan in central Iran and avoids the Alvand massif. Nahavand also lies on the branch of the Gamasab river which comes from the southeast from the vicinity of Borujerd; from Nahavand the Gamasab river flows westwards to Mount Behistun. Given Nahavand's location, it was the site of several battles, and was considered important in Iranian history during Iran's wars with its western neighbors. Climate Nahavand has a dry summer humid continental climate (Köppen climate classification Dsa). Prehistory 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 from at least 5,000 BC to BC. History During the Achaemenid period (550–330 BC), Nahavand was located in the southernmost part of Media, on the