The book festival is a one-day celebration of books, writing, reading, and publishing. It is held annually in July at the beautiful Mammoth Museum at Hayden Cabin in Mammoth Lakes, California, on the Eastside of the Sierra Nevada.  The book festival is a one-day celebration of books, writing, reading, and publishing. It includes speakers, books for sale and to give away, food, music, lawn games, and coffee! Entrance is free.