The Isle of Almaren, in the midst of a great lake in Middle-earth, was the first dwelling place of the Valar, during the Age of the Lamps. It was situated in the central part of the world, where the light of the Lamps of the Valar mixed.

It was an idyllic island realm, with green grass surrounding the dwellings of the Valar. It was here that Nessa wed Tulkas.

However, the isle was destroyed when Melkor destroyed the Lamps and cast Middle-earth down into darkness.

Their land in ruins, the Valar left Middle-earth, and moved to Valinor, where they lit the land with the Two Trees.
Encyclopedia entry originally written by High_King_Of_Gondor