Journey to the Centre of the Earth / Jules Verne

"Journey to the Centre of the Earth" is an 1864 science-fiction novel by Jules Verne. The story involves a professor who leads his nephew and hired guide down a volcano in Iceland to the 'centre of the Earth'. They are involved in many adventures, encountering prehistoric animals and natural hazards, and eventually come to the surface again in southern Italy. Verne's own belief, expressed in the novel as the viewpoint of a character, is that the inside of the Earth does in fact differ from that which the characters encounter.