Elias Lönnrot's 'Kalewala' is a monumental work of Finnish literature that combines epic poetry and folklore to create a rich tapestry of myths and legends. The book is structured as a collection of traditional oral poems woven together to tell the story of the Finnish people and their ancient heroes. Lönnrot's lyrical style captures the essence of the mystical Finnish landscape and the struggles of its inhabitants, making 'Kalewala' a foundational text in Finnish literature. The epic nature of the work, with its sprawling narrative and intricate character interactions, places it in the realm of classical epic poetry like the 'Odyssey' or the 'Edda'.