In the fiction of J. R. R. Tolkien, the Years of the Sun are the last of the three great time-periods of Arda, together with the Years of the Lamps and the Years of the Trees. They begin with the Return of the oldor to Middle-earth, and last until the present day. (The history of the fictional Middle-earth is to be taken fictionally as a history of the real Earth.) They are divided into several Ages; Tolkien only describes the First, Second, and Third Ages, and part of the Fourth, but he does say that we are living in the sixth or seventh.ja:太陽の時代 (トールキン)