"The Polar Express" is a children's book written by Chris Van Allsburg that tells the story of a young boy who embarks on a magical train journey to the North Pole on Christmas Eve. The train, called the Polar Express, is filled with children who are all excited to meet Santa Claus and experience the wonders of the holiday season. The story emphasizes themes of belief and the spirit of Christmas. As the boy travels to the North Pole, he learns about the importance of faith and the joy of giving. The book has also been adapted into an animated film, further popularizing its enchanting narrative.