Tolkien prepared several maps of Middle-earth. Some were published in his lifetime. The main maps are those published in The Hobbit, The Lord of the Rings, The Silmarillion, and Unfinished Tales, and appear as foldouts or illustrations. Tolkien insisted that maps be included in the book for the benefit of readers, despite the expense involved. The definitive and iconic map of Middle-earth was published in The Lord of the Rings, and refined by the illustrator Pauline Baynes into a stand-alone poster, A Map of Middle-earth.