A timeless fable about unity and breaking down barriers, from four-time Caldecott Honor-winner Leo Lionni.All her life Tillie the mouse has wondered what lies on the other side of the wall. Imagining all sorts of fantastic possibilities, she digs a tunnel to get to the other side, where she discovers . . . other mice, just like her! Together, Tillie and her friends work to bring down the wall and unite mouse-kind. Written just before the fall of the Berlin wall, this seemingly simple fable has a powerful message for all children—and all people.