entrance to a tunnel in a sheer cliff on the transfagaras highway in romania.

alpine altitude artificial beautiful carpathians cliff concrete construction dam electric energy entrance europe fagaras fagarash high highlands highway hydraulic hydro hydroelectric hydropower industry lake landmark landscape mountain mountains nature outdoor outdoors power reservoir road rock rocky romania scenery scenic sheer spectacular station stone storage structures technology transfagaras transfagarasan transfagarash transylvania tunnel valley vidraru wallachia water waterworks way wilderness