Nurtalë Valinóreva

After Melkor's destruction of the Two Trees, and the Darkening of Valinor, the Valar were determined to protect their realm from destruction, and raised defences against any further attack. The peaks of their eastern mountain-fence, the Pelóri, were increased to reach impassable heights, and a constant guard was set along their length, except for the single Pass of Light where the remaining Noldor dwelt in Tirion. The Valar also contrived a maze of islands, known as the Enchanted Isles among the Shadowy Seas, that would entrap or turn back any mariner from the Outer Lands attempting to cross the Great Sea into the West.

Though Valinor was hidden at this time, it still remained within the world. Long after the Hiding, aided by the power of a Silmaril, one Mariner's vessel was able to pass the Enchanted Isles and reach the shores of Aman. The captain of that vessel was Eärendil, and his embassy to Valinor marked the beginning of the ultimate downfall of Morgoth.