Nera (Danube) basin and it is not navigable. After the filling of the artificial Lake Đerdap, as a result of the Iron Gate I Hydroelectric Power Station which was finished in 1972, the mouth of the river into the Danube was flooded. In order to allow the optimal electricity production, the water level of the Nera at the mouth should not go below , while it must not exceed it if the flooding of the banks is to be avoided. Since the mid-1990s, there are significant problems in fixing the river's level, as the process is costly and complicated. In 2018, representatives
Rossola nera Rossola nera Rossola nera is a red Italian wine grape variety that has been growing in the Valtellina region of Lombardy since at least the 17th century. In 2004 DNA profiling determined that the grape has a parent-offspring relationship with the Piedmont wine grape Nebbiolo though which variety is the parent and which is the offspring is not yet clear. However, most ampelographers believe that Nebbiolo is likely the parent variety since written records in Piedmont have noted Nebbiolo being grown since at least the 13th century. An early 17th century Latin text list Rossola nera, under the synonym "Rossoladure",