Nera

The Nera is a 124-kilometre-long river running through Romania and Serbia. It is a left tributary of the Danube, which it joins near Banatska Palanka. Its length is 143 km and its basin size is 1,380 km2 . The Nera is not navigable.The Nera rises in the Semenic mountains, the easternmost part of the Banat region, south of the city of Reșița, in the Caraș-Severin County of Romania. Its source is near the mountain resort Semenic, from where it flows south. Its uppermost part, upstream from the confluence with the Nerganița, is also called Nergana. Reaching the village of Borlovenii Vechi, the Nera turns southwest, flowing between the Semenic and Banat Mountains. In this section, the Nera receives its left tributary, the Rudăria, and passes next to many villages , until it reaches Șopotu-Nou, where it sharply turns to the northwest, still curving around the Semenic mountains. It passes next to the villages of Sasca Română, Sasca Montana, Slatina Nera and Naidăș, at which point it becomes the border between Romania and Serbia for the remaining 27 kilometres .

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