Iran Officially Islamic Republic of Iran, republic in southwestern Asia. Iran is bordered on the north by Armenia, Azerbaijan, Turkmenistan, and the Caspian Sea; on the east by Afghanistan and Pakistan; on the south by the Gulf of Oman, the Strait of Hormuz, and the Persian Gulf; and on the west by Iraq and Turkey. The area of Iran is about 1,648,195 sq km. Until the 1930s Iran was known abroad as Persia. The capital and largest city is Tehran (Teheran). Tehran, is the latest and the largest capital city in the 5000-year history of Persia, as Iran was called by many people in the West before 1935. The original settlement of Tehran, north of the ancient city of Rey, may have been founded as early as the 4th century. By the early 13th century it was a small village. In 1221 invading Mongols led by Genghis Khan destroyed Rey, but Tehran survived and grew slowly in the following centuries. During the reign of the Safavid shah Tahmasp (1524-1576) a wall and four watchtowers were built around the city, and by the early 17th century Tehran had about 3000 houses. In the 1720s Afghan invaders attacked Tehran.The town defeated the initial Afghan force but fell to the main Afghan army and suffered tremendously under their occupation from 1723 to 1729. Nadir Shah freed Tehran in 1729.
In 1788 Agha Mohammad Khan, founder of the Qajar dynasty, made Tehran his capital, inaugurating the modern history of Tehran. At this time Tehran’s population was estimated to be 15,000. Under the Qajar dynasty (1786-1925), Tehran grew in population and size, and new administrative buildings, palaces, mosques, and garrisons were constructed. Capital of the immense Province of Khorasan. Located in an altitude of 985 m above see level, Mashad as the country’s second largest town, has for centuries been an important trade center and junction point on caravan routes and highways from India to Iran. Mashad grew around the legendary martyrdom of Imam Reza, and the city’s history is inextricably linked with that of his Shrine. However, the Shrine of Imam Reza and the surrounding buildings do together compromise one of the marvels of the Islamic world. Perhaps there is no other group of buildings in the world which give such an effect of opulence. A gold dome, two gold minarets, two huge gold ivans, massive silver and gilt doors.