state of the Shiraz-based dynasty. Shiraz developed into the largest and most prosperous city of Fars and an important economic and cultural center of the caliphate. Adud al-Dawla had a large library, a hospital and several mosques, bazaars, caravanserais, palaces and gardens built in the city, while south of it he erected a fortified camp for his troops, known as Kard Fana Khusraw, in 974. One of the congregational mosques built by Adud al-Dawla has survived until the present day. Two Zoroastrian fire temples also existed in Shiraz, catering to the Persians who had not converted to Islam. One of Adud al-Dawla's palaces stretched out for nearly three miles and consisted of 360 rooms. Under the Buyids, Shiraz was divided into twelve quarters and had eight gates. It owed its economic prosperity to the booming agricultural trade of Fars. The city largely consumed the agricultural products of the province, including grapes, linen, wool, cotton, collyrium, rose, violet and palm-blossom water. It was also a market for rug weavers and painters to sell their pricey products, a testament to the residents' wealth. At the time, wine, grains, gold and silver were exported from the Farsi port cities of Siraf and Najairam. Adud al-Dawla patronized scientific, medical and Islamic religious research in Shiraz. The city was spared destruction by the invading Mongols, when its local ruler offered tributes and submission to Genghis Khan. Shiraz was again spared by Tamerlane, when in 1382 the local monarch, Shah Shoja agreed to submit to the invader. In the 13th century, Shiraz became a leading center of the arts and letters, thanks to the encouragement of its ruler and the presence of many Persian scholars and artists. For this reason the city was named by classical geographers Dar al-'Elm, the House of Knowledge. Among the Iranian poets, mystics and philosophers born in Shiraz were the poets Sa'di and Hafiz, the mystic Ruzbehan, and the philosopher Mulla Sadra. Thus Shiraz has been nicknamed "The Athens of Iran". As early as the 11th century, several hundred thousand people inhabited Shiraz. In the 14th century Shiraz had sixty thousand inhabitants. During the 16th century it had a population of 200,000 people, which by the mid-18th century had decreased to only 55,000. Safavid era In 1504, Shiraz was captured by the forces of Ismail I, the founder of the Safavid dynasty. Throughout the Safavid empire (1501–1722) Shiraz remained a provincial