As we all know, Legolas had tremendous loyalty towards his friends. Although the following quote is actually from Treebeard in "The Return of the King", I'm going to misappropriate it:

For the world is changing: I feel it in the water, I feel it in the earth, and I smell it in the air. I do not think we shall meet again.

To Legolas she sent this word:

Legolas Greenleaf long under tree
In joy thou hast lived. Beware of the Sea!
If thou hearest the cry of the gull on the shore,
Thy heart shall then rest in the forest no more.'

Legolas paused and sighed, and turning his eyes southward softly he sang:

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!_

'Green are those fields in the songs of my people; but they were dark then, grey wastes in the blackness before us. And over the wide land, trampling unheeded the grass and the flowers, we hunted our foes through a day and a night, until we came at the bitter end to the Great River at last.

'Then I thought in my heart that we drew near to the Sea; for wide was the water in the darkness, and sea-birds innumerable cried on its, shores. Alas for the wailing of the gulls! Did not the Lady tell me to beware of them? And now I cannot forget them.' -- (from ROTK)

And now Legolas fell silent, while the others talked, and he looked out against the sun, and as he gazed he saw white sea-birds beating up the River.

'Look!' he cried. 'Gulls! They are flying far inland. A wonder they are to me and a trouble to my heart. Never in all my life had I met them, until we came to Pelargir, and there I heard them crying in the air as we rode to the battle of the ships. Then I stood still, forgetting war in Middle-earth; for their wailing voices spoke to me of the Sea. The Sea! Alas! I have not yet beheld it. But deep in the hearts of all my kindred lies the sea-longing, which it is perilous to stir. Alas! for the gulls. No peace shall I have again under beech or under elm.'

'Say not so!' said Gimli. 'There are countless things still to see in Middle-earth, and great works to do. But if all the fair folk take to the Havens, it will be a duller world for those who are doomed to stay.'

'Dull and dreary indeed!' said Merry: 'You must not go to the Havens, Legolas. There will always be some folk, big or little, and even a few wise dwarves like Gimli, who need you. At least I hope so. Though I feel somehow that the worst of this war is still to come. How I wish it was all over, and well over!' -- (from ROTK)

'And I,' said Legolas, 'shall walk in the woods of this fair land, which is rest enough. In days to come, if my Elven-lord allows, some of our folk shall remove hither; and when we come it shall be blessed, for a while. For a while: a month, a life, a hundred years of Men. But Anduin is near, and Anduin leads down to the Sea. To the Sea!

To the Sea, to the Sea! The white gulls are crying,
The wind is blowing, and the white foam is flying.
West, west away, the round sun is falling.
Grey ship, grey ship, do you hear them calling.
The voices of my people that have gone before me?
I will leave, I will leave the woods that bore me;
For our days are ending and our years failing.
I will pass the wide waters lonely sailing.
Long are the waves on the Last Shore falling,
Sweet are the voices in the Lost Isle calling,
In Eressëa, in Elvenhome that no man can discover,
Where the leaves fall not: land of my people for ever!'_

And so singing Legolas went away down the hill. -- (from ROTK)

After the fall of Sauron, Gimli brought south a part of the Dwarf-folk of Erebor, and he became Lord of the Glittering Caves. He and his people did great works in Gondor and Rohan. For Minas Tirith they forged gates of _mithril _and steel to replace those broken by the Witch-king. Legolas his friend also brought south Elves out of Greenwood, and they dwelt in Ithilien, and it became once again the fairest country in all the westlands -- (from LOTR Appendices)

But when King Elessar gave up his life Legolas followed at last the desire of his heart and sailed over Sea. Here follows one of the last notes in the Red Book

We have heard tell that Legolas took Gimli Glóin's son with him because of their great friendship, greater than any that has been between Elf and Dwarf. If this is true, then it is strange indeed: that a Dwarf should be willing to leave Middle-earth for any love, or that the Eldar should receive him, or that the Lords of the West should permit it. But it is said that Gimli went also out of desire to see again the beauty of Galadriel; and it may be that she, being mighty among the Eldar, obtained this grace for him. More cannot be said of this matter. -- (from LOTR Appendices)

In this year on March 1st came at last the Passing of King Elessar. It is said that the beds of Meriadoc and Peregrin were set beside the bed of the great king. Then Legolas built a grey ship in Ithilien, and sailed down Anduin and so over Sea; and with him, it is said, went Gimli the Dwarf. And when that ship passed an end was come in the Middle-earth of the Fellowship of the Ring. -- (from LOTR Appendices)

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