The Maritsa, Meriç or Evros is a river that runs through the Balkans in Southeast Europe. With a length of , it is the longest river that runs solely in the interior of the Balkans, and one of the largest in Europe by discharge. Its drainage area is about, 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, flowing southeast between the Balkan and Rhodope Mountains, past Plovdiv and Parvomay to Edirne, Turkey. East of Svilengrad, Bulgaria, the river flows eastwards, forming the border between Bulgaria and Greece, and then between Turkey and Greece. At Edirne, the river flows through Turkish territory on both banks, then turns towards the south and forms the border between Greece on the west bank and Turkey on the east bank to the Aegean Sea. Turkey was given a small sector on the west bank opposite the city of Edirne. The river enters the Aegean near Enez, where it forms a river delta. The Tundzha is its chief tributary; the Arda is another one. The lower course of the Maritsa/Evros forms part of the Bulgarian–Greek border and most of the Greek–Turkish border. The upper Maritsa valley is a principal east–west route in Bulgaria. The unnavigable river is used for power production and irrigation. The places that the river flows through include Pazardzhik, Plovdiv, Parvomay, Dimitrovgrad and Svilengrad in Bulgaria, Edirne in Turkey and Kastanies, Pythio, Didymoteicho and Lavara in Greece. There are a number of bridges over the river, including the one at Svilengrad, the one west of Edirne in Turkey and GR-2 with the D110/E90 further south and as its border crossings.
Etymology
The earliest known name of the river is Euros. Indo-European *ewru and Ancient Greekεύρύs meant "wide". The Indo-European "wr" sound shifted in Thracian to "br", creating the Thracian name Ebros. Thereafter, the river began to be known as Hebros in Greek and Latin. Rather than an origin as "wide river", an alternative hypothesis is that Hebros meant "goat" in Thracian. The Ebro river in Spain is the one having the more important flow, name seems corresponding to an old root meaning 'drink', as in Spanish term for 'drunk': 'ebrio'; in an identical way, some Spanish rivers today have the name: Rio Flumen, Latin for 'River, water flow', a trace of rivers having similar names to Ibar, Ivrea, Ibor, can be found in the way from Transcaucasian Iberia to Iberian peninsula. The Latin for drinking 'bibendum' may just mean 'ending seeing double' Since, when first attested, Europe referred only to Thrace proper, the name of the continent is possibly derived from this river. While the name Έβρος was used in Ancient Greek, the name Μαρίτσα had become standard before the ancient form Έβρος was artificially restituted in Modern Greek. The name Maritsa may derive from a mountain near the mouth of the river known in antiquity as Μηρισός or Μήριζος, Latinized as Meritus.
The Maritsa/Evros river as a natural barrier on the border between Turkey and Greece has become a major route for migrants from a variety of countries attempting to enter the EU illegally. At the height of the 2010s migrant crisis, in 2012, a border barrier was erected on the Greek side in order to prevent illegal crossings into Greece and thus into the EU. Following the heavy lossesTurkish armed forces incurred at the hands of the Russian-backed Syrian government in northern Syria at the end of February 2020, a drastic change in Turkey's policy towards irregular migrants on its territory led to escalation of the situation at the Evros border crossings as well as exacerbation of tension between Turkey on one hand and Greece and the EU as a whole on the other hand. In May 2020, news emerged that Turkish forces occupied a of Greek territory, Melissokomeio, as shown on maps of 1923, following a change in the flow of the Maritsa/Evros river.
Tributaries
Starting from the river's source, significant tributaries of Maritsa include:
Left tributaries:
*Topolnitsa
*Luda Yana
*Stryama
*Sazliyka
*Tundzha/Tunca
*Ergene
Right tributaries:
*Chepinska reka
*Vacha
*Chepelarska reka
*Harmanliyska reka
*Arda/Ardas
*Erythropotamos/Luda reka
Floods
The lower course of the river Maritsa/Evros, where it forms the border of Greece and Turkey, is very vulnerable to flooding. For about 4 months every year, the low lands around the river are flooded. This causes significant economic damage, which is estimated at several hundreds million Euro. Recent large floods took place in 2006 and 2007. Several causes have been proposed: more rainfall due to climate change, deforestation in the Bulgarian part of the catchment area, increased land use in the flood plains and difficult communication between the three countries.