"Inspired by Menegroth in Doriath, and seeking a hidden place from which to be safe from the forces of Morgoth, Finrod established it in the early years of the First Age, in the Caverns of Narog beneath the forested hills of Taur-en-Faroth on the western bank of Narog. The original denizens of this huge cave system had been the Noegyth Nibin, the so-called 'Petty-dwarves', but whether they were driven out of their homes by Finrod's people, or earlier by the nearby Sindar, is not known.
Other Dwarves, stonemasons from the Ered Luin, then helped the Noldor enlarge and landscape the caves into a formidable and concealed stronghold. Originally, it could only be reached by a narrow path along the banks of the river, but later a bridge was built across Narog."
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