This book includes such beautiful illustrations, ahh! I really enjoyed reading about Tolkien's creations and this is a very comprehensive and thorough compilation of a lot of races, places and plants. If you read all of it, you get a short history of everything that happens in the Undying Lands and Middle-Earth from the creation to what happens after the destruction of the One Ring. But if you only read about certain creatures it still tells you what is most important about them and where in Tolkien's stories they appeared.
A more detailed map of Middle-Earth would have been better but the one provided included ALL of the lands and that is pretty cool.