Iran (known also as Persia) is located in the Middle East, Southwest Asia. Long and relatively high mountain ranges, amazing vast deserts in the center, dense forests in the north, Persian Gulf and Arabian coasts in the South as well as Caspian coast in North are the most notable geographical features of Iran. Iran with an area of 1648000 km2 is the 18th largest country in the world neighboring seven other countries including Turkmenistan (Northeast), Azerbaijan and Armenia (Northwest), Turkey and Iraq (West), Pakistan and Afghanistan (East). The longest land border of Iran is with Iraq (1458 km) and the shortest is with Armenia (35 km). Besides land borders, Iran is surrounded by 2440 km coastline in the North and South. Iran population was more than 75 million people in 2010 of which more than 8 million lived in Teharn, the capital city. The other most populous cities in Iran are Mashhad, Isfahan, Karaj, Tabriz and Shiraz, respectively. Nearly 70 percent of Iranian people live in the urban areas. Iran is rich in terms of Nomadic life. According to 2007 census, the population of nomadic tribes in Iran is close to 1200000 people. Ethnically they are very diverse and, therefore, scattered around the country. The major nomadic tribes in Iran are Bakhtiaris, Qashqayis, Shahsavan and Kurdish tribes. Our country has a rough topography with two major mountain ranges surrounding the central basin. Zagros is the main mountain range which stretches from Northwest to Southeast. The majority of the peaks of the Zagros range are more than 3000 m high and their height increases in the South which exceeds 4000 m. The other mountain range is Alborz stretching from Northwest to Northeast. This relatively narrow range enjoys higher peaks including the tallest mountain in Iran, Damavand, which is 5671 m high. This peak is highly important in aesthetic, mythological and historical terms. The majority of central Iran is covered with various desert landscapes. In eastern part of Iranian plateau, there is Great Desert of Kavir to whose south Lut Desert is located. Except for few oases, these deserts are uninhabited. Iran has two main plains. One of them is Khuzestan Plain that is located in Southwest Iran and the other is in North of the country in southern coastline of Caspian Sea. These Plains are very fertile leading to the economic prosperity these regions. Though Iran has quite many permanent and seasonal rivers, it doesn’t have any major river. However, the longest and the biggest river in Iran is Karoun (830 km/515 miles long) located in Southwest of the country. Some parts of this river are navigable but only smaller vessels can sail through this river. Iran also enjoys several important lakes including Urmieh, Gahar, Bakhtegan and Zarivar scattering around the country.Iran has various climatic zones. Different climates have made Iran a country of four seasons. In the Northwest, weather is rather cold and rainy in the fall becoming very cold, sometimes even freezing, in the winter. In the spring, weather is mild and very pleasant and quite warm in the summer. In the Caspian region (in the North) including three provinces of Gilan, Mazandaran and Golestsn, weather is mild with the highest annual precipitation in Iran. As we move Southward, the warm climate dominates so that in the southern edge weather becomes extremely hot in the spring and summer but very pleasant in the late fall and winter. The central and southern regions almost always face low precipitation leading to constant drought.