The Büyük Menderes River ("Great Meander", historically the Maeander or Meander, from Ancient Greek: Μαίανδρος, Maíandros; Turkish: Büyük Menderes Irmağı), is a river in southwestern Turkey.

It appears earliest in the Catalog of Trojans of Homer's Iliad along with Miletus and Mycale.

The river has its sources not far from Celaenae in Phrygia (now Dinar),[1] where it gushed forth in a park of Cyrus.

Near Carura it passes from Phrygia into Caria, where it flows in its tortuous course through the Maeandrian plain,[8] and finally discharges itself in the Gulf of Icaros (an arm of the Aegean Sea), between the ancient Greek cities Priene and Myus, opposite to the Ionian city of Miletus, from which its mouth is only 10 stadia distant.

[11] It frequently overflows its banks and, as a result of the quantity of mud it deposits at its mouth, the coast has been pushed about 20 or 30 stadia (about 4 to 6 kilometers in modern units) further into the sea and several small islands off the coast have become united with the mainland.