Herat (Persian: هرات) is one of the thirty-four provinces of Afghanistan, located in the north-western part of the country. Together with Badghis, Farah, and Ghor provinces, it makes up the north-western region of Afghanistan. Its primary city and administrative capital is Herat City. The province of Herat is divided into about 17 districts and contains over 2,000 villages. It has a population of about 3,780,000, making it the second most populated province in Afghanistan behind Kabul Province. The population is multi-ethnic but largely Persian-speaking. Herat dates back to the Avestan times and was traditionally known for its wine. The city has a number of historic sites, including the Herat Citadel and the Musalla Complex. During the Middle Ages Herat became one of the important cities of Khorasan, as it was known as the Pearl of Khorasan.[1] The province of Herat shares a border with Iran in the west and Turkmenistan in the north, making it an important trading region. The Trans-Afghanistan Pipeline (TAPI) is expected to pass through Herat from Turkmenistan to Pakistan and India in the south. The province has two airports, one is the Herat International Airport in the capital of Herat and the other is at the Sabzwar Air Base, which is one of the largest military bases in Afghanistan. The Salma Dam which is fed by the Hari River is also located in this province.