Seventeen countries, from Egypt and Turkey in the west to Iran in the east and Yemen and Oman in the south, make up the Middle East as it is usually defined: Egypt plus West Asia, minus the Caucasus. Together they cover roughly 7.3 million km², sitting where Africa, Europe and Asia meet. The region’s main physical units are the plateau and mountains of Anatolia, the Levant on the eastern Mediterranean, the river plain of Mesopotamia, the Arabian Peninsula (at 3,237,500 km² the largest peninsula in the world) and the Iranian Plateau, plus Egypt’s Nile valley and Sinai. Its highest point is Mount Damavand in Iran at 5,610 m; its lowest is the shore of the Dead Sea, about 440 m below sea level in 2025. The main rivers are the Nile, the Tigris and the Euphrates, which at about 2,780 km is the longest river in West Asia. Most of the region is hot and arid, and Saudi Arabia is its largest country by area.
The clearest way to fit those pieces together is to follow the Euphrates from its mountain sources in eastern Turkey, through Syria and Iraq, to the Persian Gulf. The river crosses or skirts almost every landform type in the region, and each stop along it opens a view onto the neighbouring regions.
Kara Su and Murat: Starting High in the Armenian Highlands
The Euphrates begins as two rivers. The Kara Su, or Western Euphrates, and the Murat Su, or Eastern Euphrates, both rise north-west of Lake Van, at about 3,290 m and 3,520 m. They run for about 450 km and 650 km respectively before joining some 10 km upstream of the town of Keban. This is the Armenian Highlands, the cold, high north-eastern corner of the Middle East, where rain and melting snow supply most of the river’s water. Discharge peaks in April and May with the snowmelt.
Two landmarks frame the start of the journey. Lake Van, the largest lake in Turkey, covers 3,755 km² at 1,640 m above sea level. It has no outlet: lava flows from the Nemrut volcano blocked its old one towards the Murat, and its water is a saline soda solution. Further east, Greater Ararat, a dormant volcano, reaches 5,137 m, the highest peak in Turkey, and stands close to the meeting point of Turkey, Iran, Armenia and Azerbaijan’s Nakhchivan exclave. Ararat is the tallest summit on the route, but not in the region: Damavand, a dormant volcano in Iran’s Alborz range, is higher still.
Keban to Birecik: Through the Taurus Gorges
Below the confluence, the Euphrates cuts south through the Southeastern Taurus, the eastern end of the mountain arc that separates the Mediterranean coast from the Anatolian Plateau. The drop is steep. At the Keban Dam, completed in 1974 as the first of Turkey’s big Euphrates dams, the river stands at 693 m. Over the next 600 km or less to the Syrian border it falls another 368 m.
That gradient made this stretch the heart of the Southeastern Anatolia Project (GAP), a scheme planned at 22 dams and 19 power plants on the Euphrates and Tigris, affecting about 75,000 km². Its largest structure is the Atatürk Dam, about 55 km north-west of Şanlıurfa, completed in 1992. Its reservoir is the third-largest lake in Turkey and can hold 48.7 km³, enough to store the river’s entire annual flow. Downstream, the reservoir of the Birecik Dam drowned most of the villages of Halfeti district in the 1990s and flooded the Roman mosaics of Zeugma. Building the GAP dams affected 382 villages and resettled almost 200,000 people, including 55,300 for the Atatürk Dam alone.
Euphrates Lake and the Syrian Bend: A Detour to the Levant Rift
The river enters Syria near Jarabulus and swings east in a broad bend. Here three tributaries join it from the Taurus foothills: the Sajur, the Balikh, which meets the Euphrates at Raqqa, and the Khabur, the largest of the three, which joins near Busayrah. They are the last natural tributaries the river receives. The Tabqa Dam, finished in 1973, holds back Euphrates Lake, formerly Lake Assad, Syria’s largest lake, with a maximum surface of 525 km² and a capacity of 11.7 km³. It irrigates land on both banks and supplies drinking water to Aleppo.
From the top of the bend, the Levant lies to the west. Its backbone is the Jordan Rift Valley, a long basin running from the sources of the Jordan River through the Hula Valley and the Sea of Galilee to the Dead Sea, then on through the Arabah to the Gulf of Aqaba. The Dead Sea, bordered by Jordan, the West Bank and Israel, has the lowest land surface on Earth: its water stood 439.78 m below sea level in 2025. At 304 m deep it is the deepest hypersaline lake in the world, and it is shrinking fast, from 1,050 km² in 1930 to about 605 km² today. Along the Mediterranean coast, the Levant has a relatively temperate climate, with dry summers and cool, wet winters.
Deir ez-Zor to Hīt: Where the Syrian Desert Meets Arabia
Below Raqqa, the land on both banks turns to steppe, then desert. South and west of the river stretches the Syrian Desert, about 500,000 km² of gravel and rocky desert pavement cut by dry wadis, covering about 85% of Jordan and 55% of Syria and reaching into Iraq and Saudi Arabia. Its centre is the Hamad, a flat, stony limestone plateau 700 to 900 m high, where what little rain falls drains into salt flats.
To the south, the Syrian Desert merges into the Arabian Peninsula. Seven countries lie wholly on it: Saudi Arabia, Yemen, Oman, the United Arab Emirates, Qatar, Bahrain and Kuwait, along with the southern parts of Iraq and Jordan. The peninsula formed between 56 and 23 million years ago as the Red Sea Rift split the Arabian plate from Africa. Its southern third is the Rub’ al Khali, the Empty Quarter, about 650,000 km² of dunes and gravel plains across Saudi Arabia, Oman, the UAE and Yemen. Its dunes rise up to 250 m, and the surface falls from 800 m in the south-west to near sea level in the north-east.
The river’s own gradient tells the story of the plain ahead. In all of Syria the Euphrates drops 163 m. Between Hīt in western Iraq and the Shatt al-Arab it drops only 55 m.
Baghdad’s Doorstep: The Mesopotamian Plain and the Zagros Wall
In central Iraq the Euphrates enters Mesopotamia proper, the “land between the rivers”. Its partner, the Tigris, is 1,750 km long. It rises in the Taurus about 25 km south-east of Elazığ, only some 30 km from the Euphrates valley, and flows past Mosul, Tikrit and Samarra to Baghdad. The two rivers built this alluvial plain from their silt, and it forms the eastern end of the Fertile Crescent, the arc of farmland that continues west through the Levant. Water control is old here. The Hindiya Barrage of 1913 was the first modern diversion structure on the river system, and the Ramadi Barrage sends floodwater into Lake Habbaniyah.
East of the plain rises the Zagros, a 1,600 km wall of mountains that runs from north-west Iran through Iraqi Kurdistan to the Strait of Hormuz, with more than 40 summits above 4,000 m in the Dena sub-range alone. The Zagros formed as the Arabian plate pushed into the Eurasian plate, mostly in the Miocene, and the collision continues: GPS measurements show the range and the Iranian Plateau behind it are still rising. The plateau stretches east across Afghanistan to the Sulaiman Mountains of Pakistan, with the Caspian Sea and the Köpet Dag on its northern edge; Damavand rises in the Alborz, close to the Caspian shore.
Al-Qurnah to Hormuz: Marshes, the Shatt al-Arab and the Gulf
Before the two rivers meet, they spread into the Mesopotamian Marshes, bounded by Basra, Nasiriyah and Amarah and spilling into south-west Iran and northern Kuwait. The Central, Hawizeh and Hammar marshes once covered about 20,000 km² and formed the largest wetland ecosystem in western Eurasia, home to the Marsh Arabs, whose livelihood rests on reed-cutting, fishing and water buffalo. Engineers started draining them in the 1950s, and Saddam Hussein’s government pushed the work much further in the late 1980s and 1990s; by 2003 the marshes had shrunk to about 10% of their original area. They have partly recovered since and four of their wetland areas were inscribed on the UNESCO World Heritage List in 2016, though drought and upstream dams in Turkey, Syria and Iran slow the recovery.
At al-Qurnah the Euphrates and Tigris join to form the Shatt al-Arab, about 200 km long and 232 m wide at Basra. Its lower course forms the Iran–Iraq border, and Iran’s Karun joins it from the east, carrying so much silt that the channel must be dredged constantly. In the mid-1970s its banks held 17 to 18 million date palms, the largest date-palm forest in the world; by 2002 war, salt and pests had killed more than 14 million of them.
The river ends in the Persian Gulf (called the Arabian Gulf by Arab governments), a shallow inland sea of about 251,000 km² and 989 km long, with Iran along most of its northern shore and Saudi Arabia along most of its southern one. The gulf basin began filling about 15,000 years ago as sea levels rose after the last glaciation. Its only outlet is the Strait of Hormuz, between Iran and Oman’s Musandam Peninsula, which varies from about 97 km to 39 km wide. In 2023–2025 about a quarter of the world’s seaborne oil trade and a fifth of its liquefied natural gas passed through it each year. The trip from the snows above Lake Van to that strait crosses most of the region, from highland to desert to the Gulf; for the river itself, read the Euphrates river guide, then follow the side trips to the Mesopotamian Marshes and the Dead Sea, or count the region’s states in how many countries are in the Middle East.