The Years of the Sun were the last of the three great time-periods of Arda. They began with the first sunrise in conjunction with the return of the Noldor to Middle-earth, and last until the present day. The Years of the Sun began towards the end of the First Age of the Children of Ilúvatar and continued through the Second, Third, and part of the Fourth in Tolkien's stories. Tolkien estimated that modern times would correspond to the sixth or seventh age.