Its source is on Mount Rila in Bulgaria and it flows in the sea region of Thasos, where the Nestos Delta is formed. The river flows from North to South and from West to the East. It crosses the massif of Western Rodopi and the mountain Falakro and flows into the Thracian Sea, opposite Thasos. Its flow forms the border between Macedonia and Thrace and the Prefectures of Kavala and Xanthi, after first flowing through the Prefecture of Drama. It is one of the five largest rivers of Greece and its total course covers 243 km, of which approximately 130 km are on Greek territory. The largest tributaries of Nestos are Despatis, the Limonas stream, Diavolorema and Arkoudorema.
In its rus, there are two hydroelectric dams, the dam of Thisauros and the dam of Platanovrisi which have created two lacustrine, longitudinal rivers. Between the mountain massifs of Rodopi, the famous “Nestos Straits” are formed.
Nestos Straits and the International mountaineering trail E6
Nestos Straits (or valley). It is a region of total area of 23.800 acres with approximately20km length, covered in rich vegetation. The great river crosses it creating a surreal image of calmness and awe. In its course, it collects the waters of dozens of rivers and streams, creating a varied hydrographic network with significant water ecosystems. The fish fauna is remarkable (mountain trout, mullet etc.) and rich riverside vegetation (oak trees, alders, willows, plane trees, poplars, ash trees). The Nestos Delta is famous for its rare riverside forest, also known as Megalo Dasos (Koca Orman). The Nestos Straits are included in the wetlands of Natura 2000.
From the village Galani, a branch of the international mountaineering trail E6 starts (it begins in Sweden, crosses Europe until the Adriatic Coast and then enters Greece from Igoumenitsa and ends in Samothrace). The trail follows the eastern side of Nestos, passes Livera and ends in Stavroupoli. The trail E6 coincides with the old railway trail which was built in 1893 to facilitate the staff because the Straits on the eastern bank of Nestos are too steep and rocky and the transfer of workers and construction material for the railway line was impossible. Until today, i.e. for over a century, the Straits visitors use the same trail as the railway people.
The route is indicated for trekking.
It is part of the National Park of East Macedonia and Thrace; it is the largest wetland park of the country with 22 lagoons.
The Nestos Delta with a total area of almost 550.000 acres is the natural border between the Prefectures of Xanthi and Kavala.
Its origins are situated at its exit from the mountain range of Rodopi (Nestos Straits), at the height of Toxotes and extends up to the Thracian Sea.
The lagoons, the reed beds, the sand dunes, the riverside forest, the areas inundated by sea water compose a unique mosaic.
The richness of wildlife is huge. In the remaining famous Kotza Orman (Big or Legendary Forest), the only aquatic forest in Europe, there are large mammals, like wild boar, wolves, jackals, otters, badgers, foxes, martens and weasels. It is still particularly rich regarding the feathered world. In the Nestos Delta 254 bird species have been recorded, among them rare and endangered species. It is the most important region in Greece for the reproduction of Vanellus spinosus and the only place in the European area where the Phasianus colchicus can be found in natural conditions.
The number of jackals (Canis aureus) living and reproducing in the Nestos Delta is also significant. Some of the residents of the area have reported seen a Lynx lynx, one of the rarest mammals, but its last official sighting was many decades ago.
The route is indicated for biking.