Ardabil is a historical city in north-western Iran. The name Ardabil comes from the Zoroastrian name of "Artawila", which means a holy place. At the 2011 census, its population was 564,365, where the dominant majority are ethnic Azeris. Notable for its silk and carpet trade tradition, the ancient Ardabil Carpets are considered some of the best of the classical Persian carpet creations. Ardabil is also known as the seat of a World Heritage Site: the sanctuary and tomb of Shaikh Safî ad-Dîn, eponym of the Safavid Dynasty. The province is believed to be populated since the Achaemenids Dynasty (ca. 550–330 BC). It is mentioned in the Avesta, where prophet Zoroaster was born by the river Aras and wrote his book in the Sabalan Mountains. During the Parthian era, the city had a special importance among the cities of Azarbaijan. Some Muslim historians attribute the foundation of Ardabil to king Peroz I of the Sassanid Empire. The Persian poet Ferdowsi also credits the foundation of the city to Peroz I. Ardabil suffered some damages caused by occasional raids of Huns from 4th to 6th century AD. Peroz repaired those damages and fortified the city. Peroz made Ardabil the residence of provincial governor (Marzban) of Azarbaijan. During the Islamic conquest of Iran, Ardabil was the largest city in north western Iran, and remained so until the Mongol invasion period. Incursions of Mongols and Georgians left the city in ruins for nearly three centuries until the advent of Safavids. Safavid Shah Ismail I started his campaign to nationalize Iran's government and land from there, but consequently announced Tabriz as his capital in AD 1500. Yet Ardabil remained an important city both politically and economically until modern times.