The Return of the King, “The Last Debate”. Legolas sang this when recounting to Merry and Pippin their ride with Aragorn over the plains of Lebennin.

Silver flow the streams from Celos to Erui
In the green fields of Lebennin!
Tall grows the grass there. In the wind from the Sea
The white lilies sway,
And the golden bells are shaken of mallos and alfirin
In the green fields of Lebennin,
In the wind from the Sea!

Provided by: NenyaGold