Land

Iran consists mainly of mountain ranges encircling a high central plateau, sometimes called the Plateau of Iran. The Elburz Mountains in the north and northwest ring the shore of the Caspian Sea. In this range rises Damavand, a dormant volcano that crests at 18,606 feet (5,671 m)—highest elevation in the nation. In the west and southwest are the Zagros Mountains with numerous peaks reaching elevations of 13,000 to almost 15,000 feet (4,000 to 4,600 m). Lower mountains occur in the northeast, east, and southeast, mainly along the outer margins of the country.

Nearly all the rest of Iran is occupied by the central plateau, 3,000 to 5,000 feet (900 to 1,500 m) above sea level. Mountain ranges divide this region into a number of basins containing gravelly and salt-encrusted deserts, largest of which are Dasht-e Kavir and Dasht-e Lut. The only lowlands are along the coasts of the Caspian Sea, the Gulf of Oman, and the Persian Gulf, especially the northern section.

Water

Virtually all of Iran's permanent rivers flow to the Caspian Sea or the Persian Gulf from the Zagros, Elburz, and Kopet Dagh mountains. There are few rivers in eastern Iran, where streams are generally intermittent and end in inland basins. The Karun River in the southwest is the only navigable river; it flows into the Shatt al Arab. Lake Urmia, which is salty and shallow, is the country's largest lake.

Climate

Iran has a continental climate, with hot summers and cold to mild winters, abundant sunshine, and strong winds. Summer heat is intense along the shores of the Persian Gulf and the Gulf of Oman, with temperatures sometimes rising above 120° F. (49° C.). Winter is coldest in the high mountains and on the plateau. Relatively mild winters occur along all the coasts. Most of the country receives scant rainfall; what rain does occur comes mainly during the winter and spring months. The heaviest precipitation—more than 40 inches (1,020 mm) per year—occurs in parts of the Elburz and Zagros mountains. The eastern deserts receive virtually no precipitation.