Jules Verne
A Journey to the Center of the Earth, also translated as A Journey to the Interior of the Earth, follows a man, his nephew and their guide down an Icelandic volcano into the center of the earth. There they encounter an ancient landscape filled with prehistoric animals and natural dangers. There is some discussion as to whether Verne really believed that such things might be found in the center, or whether he shared the alternate view,
...Although The Mysterious Island is technically a sequel to Vernes' enormously popular Twenty Thousand Leagues Under the Sea, this novel offers a vastly different take on similar thematic motifs. As with all of Verne's best-known works, The Mysterious Island is a masterpiece of the action-adventure genre, with a heaping dash of science fiction influence thrown in for good measure.