The Maritsa, known in Greek as the Hebros and in Turkish as the Meriç, is a river that runs through the Balkans in Southeast Europe. With a length of 480 km (300 mi), it is the longest river that runs solely in the interior of the Balkan peninsula, and one of the largest in Europe by discharge. It flows through Bulgaria in its upper and middle reaches, while its lower course forms part of the border between Greece and Turkey. Its drainage area is about 53,000 km (20,000 sq mi), of which 66.2% is in Bulgaria, 27.5% in Turkey, and 6.3% in Greece. It is the main river of the historical region of Thrace, most of which lies in its drainage basin.
It has its origin in the Rila Mountains in Western Bulgaria, its source being the Marichini Lakes. The Maritsa flows east-southeast between the Balkan and Rhodope Mountains, past Plovdiv and Dimitrovgrad in Bulgaria to Edirne in Turkey. East of Svilengrad, Bulgaria, the river flows eastwards, forming the border between Bulgaria (on the north bank) and Greece (on the south bank), and then between Turkey and Greece. At Edirne, the river meets its two chief tributaries Tundzha and Arda, and flows through Turkish territory on both banks. It then turns towards the south and forms the border between Greece on the west bank and Turkey on the east bank all the way to the Aegean Sea, which it enters near Enez, forming a river delta. The upper Maritsa valley is a principal east–west route in Bulgaria. The unnavigable river is used for hydroelectric power generation and for irrigation.
