'Then he rose up, and he made a grave for Morwen above Cabed Naeramarth on the west side of the stone; and upon it he cut these words: Here also lies Morwen Eledhwen.
'It is told that a seer and harp-player of Brethil named Glirhuin made a song, saying that the Stone of the Hapless should not be defiled by Morgoth nor ever thrown down, not though the sea should drown all the land; as after indeed befell, and still Tol Morwen stands alone in the water beyond the new coasts that were made in the days of the wrath of the Valar.'
Wow, this is creepy. Have you been listening to any of the Tolkien Professor podcasts…?
"But there was in Thranduil’s heart a still deeper shadow. He had seen the horror of Mordor and could not forget it. If ever he looked south its memory dimmed the light of the Sun, and though he knew that it was now broken and deserted and under the vigilance of the Kings of Men, fear spoke in his heart that it was not conquered for ever: it would arise again."
— J.R.R. Tolkien, Unfinished Tales, “Appendix B, The Sindarin Princes Of The Silvan Elves”