Based on the works of J. R. R. Tolkien, the Valian Years are a reference to the passage of time between the first arrival of the Ainur in Arda and the first sunrise. This is a period of five thousand Valian years, or nearly 48 thousand solar years. The account in Valian years is not used when describing the events of Beleriand and Middle Earth. There are 3500 solar days in a Valian year (had there been a sun at this time to measure a solar day), or approximately 9.58 solar years in a Valian year. Valar hours are 7 times longer than standard hours. The history of J. R. R. Tolkiens fictional universe of Middle-earth is divided into three time periods, known as the Years of the Lamps, Years of the Trees and Years of the Sun. ... Ainulindalë (Quenya for Music of the Ainur or, more literally, Ainu-singing) is the first chapter of The Silmarillion, an abridged and condensed collection of fictional, mythical histories written by J. R. R. Tolkien, edited and published posthumously by his son, Christopher Tolkien. ... In the fiction of J. R. R. Tolkien, the Years of the Lamps are one of the three great time-periods of Arda. ... A map of Aman, courtesy of the Encyclopedia of Arda In J. R. R. Tolkiens Middle-earth legendarium, the Years of the Trees are one of the three great time-periods of Arda. ... 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. ... The main part of this article relates to a version of Middle-earths history that is considered canon by many Tolkien fans (see: Middle-earth canon); it may contradict parts of The Silmarillion or other texts. ... In the fiction of J. R. R. Tolkien, the First Age began with the awakening of the Elves, and ended with the final overthrow of Morgoth by the combined armies of Valinor and Beleriand. ... The Second Age is a fictional time period from J. R. R. Tolkiens universe of Middle-earth. ... The Third Age is a fictional time period from J. R. R. Tolkiens universe of Middle-earth. ... The Fourth Age is a fictional time period from J. R. R. Tolkiens universe of Middle-earth. ... The term Final Battle in this article refers to the expression used in the works of J. R. R. Tolkien. ... This article includes several timelines relating to J. R. R. Tolkiens fiction. ... J. R. R. Tolkien in 1972, in his study at Merton Street (from by H. Carpenter) John Ronald Reuel Tolkien (January 3, 1892 – September 2, 1973) is best known as the author of The Hobbit and its sequel The Lord of the Rings. ... The Holy Ones (singular Ainu), the first beings created by Ilúvatar, the order of the Valar and Maiar, made before Eä. There was Eru, the One, who in Arda is called Ilúvatar; and he made first the Ainur, the Holy Ones, that were the offspring of his thought. ... In the works of J. R. R. Tolkien, Arda is the world in which all of the events occur, including the continents of Middle-earth and Aman. ... In the fiction of J. R. R. Tolkien, Beleriand was the region of northwestern Middle-earth during the First Age. ... ... Middle-earth is the name used for the inhabitable parts of J.R.R. Tolkiens fictional Arda (ancient Earth) where the (canonical) stories in his legendarium take place. ...

See: http://www.annalsofarda.dk/Annals-of-Arda/misc/misc-reckoningoftheyears.htm