A Journey to the Interior of the Earth - Jules Verne

Journey to the Interior of the Earth is an 1864 science fiction novel by Jules Verne (published in the original French as Voyage au centre de la Terre). The story involves a professor who leads his nephew and hired guide down a volcano in Iceland to the "center of the Earth". They encounter many adventures, including prehistoric animals and natural hazards, eventually coming to the surface again in southern Italy. (Summary from wikipedia.org)