According to tradition, the Stone of the Hapless survived the inrushing seas at the end of the First Age to remain visible as an island far off the coasts of Middle-earth. That Stone lay only about thirty miles westward of Amon Obel, and at a lower elevation, so it seems plausible that the hill also survived as an island after most of the surrounding lands were consumed by the Great Sea.

Amon certainly means 'hill', but the name element Obel is not specifically explained in reference to this hill. In other contexts (for example, Radagast's old home of Rhosgobel) it means 'fenced homestead', and given the existence of the palisaded stockade of Ephel Brandir on its heights, it seems unavoidable that this is also the intended meaning here. The stockade of Ephel Brandir was not built until about the year I 495, so it seems to follow that Amon Obel must have had a different name before that time, but no earlier name for the hill is recorded.