|History of Arda|
|Timeline of Arda|
It begins with the first sunrise, in conjunction with the Return of the Ñoldor to Middle-earth, and lasts until the present day. The Years of the Sun began sometime after the destruction of the Two Trees. Afterwards, the count of time was measured according to the Sun's travels through the heavens and its change of direction and rotation. This continued throughout the rest of the Ages of the Children of Ilúvatar, including the First Age of the Children of Iluvatar, the Second, and the Third, and part of the Fourth in Tolkien's stories.