Yvresse

Yvresse is the land of mists. It encompasses not only a sizable part of eastern Ulthuan, but also the islands of the Eastern Ocean. The mainland is a wild coastline, fringed by deep coniferous forests. The foothills of the Annulii march off to form distant peaks that tower dramatically into the clouds. Yvresse is the least densely populated kingdom of Ulthuan, and by those Elves from other realms, it is often considered a bleak coastal realm, and less than lovely -- but to those who call it their home, the towering cliffs and soaring sea birds are sights as fine as any to be seen on the continent of Ulthuan.

To the east of the mainland are the Shifting Isles. This is an area shrouded in legend, where ancient spells of illusion shield the eastern coast of Ulthuan from intruders. The who area is wreathed in mists, and within these billowing clouds, strange and terrifying things are often seen; whether these are the products of men's ensorcelled imaginations or whether they actually exist is something not often discussed. However, the Shifting Isles definitely live up to their name, and each is seldom encountered twice in the same spot. This creates treacherous mazes of shoals and sandbars which can confuse even High Elf sailors.

Yvresse has only one major city: Tor Yvresse, a metropolis as beautiful and grand as any of the Elven cities of old. Sadly, its glory days are long past. Many of the old mansions are uninhabited, and the great amphitheatres are silent and empty. The walls of the city are mighty and deep, but there are never enough warriors to man them, and many wonder if the city could withstand another serious invasion.

Source

 * Warhammer Armies: High Elves (8th edition) -- p. 13