Niels Klim's Underground Travels, originally published in Latin as Nicolai Klimii Iter Subterraneum (1741), is a satirical science-fiction/fantasy novel written by the Norwegian-Danish author Ludvig Holberg.

His only novel, it describes a utopian society from an outsider's point of view, and often pokes fun at diverse cultural and social topics such as morality, science, sexual equality, religion, governments, and philosophy.

His curiosity drives him to investigate a strange cave in a mountainside above the town, which sends out regular gusts of warm air.

But, since he has considerably longer legs than the Potuans, who walk very slowly, he is set to be the Lord's personal courier, delivering letters and suchlike.

But again he is driven from hearth and home due to his tyranny and as he escapes he falls into a hole, which carries him through the crust and back up to Bergen again.