Xilvalur was the largest wood Elf home in the known world, located on the southern peninsula of the Sea of Trees up to the Wyrm's Spur. Its name likely translated to "Echo of the Deep Woods" in an ancient Sylvan dialect, though this language sounded corrupted to Elven speakers from Ardhon Miniel. Fey energy radiated around this community, though many speculated that the magic was Unseelie in nature.
Though Xilvalur's borders were somewhat undefined, moonlight shined impossible brightly on the branches of the Wood of Ara'mírë. So long as the silver light of the sky could be seen, the elves considered the forest under their dominion, but did not lay claim to places where the Sea of Trees grew thick. Lead for thousands of years by Teralis Yllaralei, it retained little contact with the outside world, uninterested in the goings-on of Aelindor or the Elthysi Sovereign.
Xilvalur's inner sanctuary held Tirion Isilmírë, one of the oldest Elven bastions in the world and the crownland's only true city. Protected by their Epochal Artifact, the Moonstone of Deepsilver, Tirion Isilmë was considered to be utterly impregnable.