Dozens of rivers are found in the Middle East (Asia). Most are small, so here we highlight the four major ones, and offer a brief description.
This river flows from a high plateau in the Pamir Mountains of central Asia, across southern Tajikistan, forming its border with Afghanistan, then northwest, forming parts of the borders between Turkmenistan and Uzbekistan and on into the Aral Sea. It's (1,578 miles) (2,539 km) in length. In ancient times the Amu Darya was called the Oxus. It was part of Persia, and played a significant role in the military campaigns of Alexander the Great.
From the Caucasus Mtns of Armenia, it flows southwesterly across east-central Turkey, then generally southeast through Syria and Iraq, ending in the waters of the Persian Gulf. It joins with the Tigris in southern Iraq, and from that junction continues on as the Shatt al Arab. Overall it's (2,235 miles) (3,596 km) in length, and is certainly the longest river in the Middle East. Historically important in ancient history, the once great city of Babylon stood on its banks.
It begins in the high mountains of Tibet (southwestern China), flowing northwest through the Jammu & Kashmir region of India and Pakistan, then generally south through Pakistan, ending in the Arabian Sea. The Indus, through a series of dams and canals, provides much of the irrigation and power for central Pakistan. It's (1,800 miles) (2,896 km) in length.
Rising in the mountains of southern Turkey, the Tigris flows southeast through Iraq, where in the southern part of that country it merges with the Euphrates to become the Shatt al Arab, which then flows to the Persian Gulf. The river has numerous small tributaries running from its eastern bank, and is (1,180 miles) (1,899 km) in length.