The Savage Land is tropical, prehistoric land hidden in Antarctica. It was created during the Triassic by the aliens for observation and research purposes. It was stocked the Land with Earthly life of the era, most notably dinosaurs; as Earth's flora and fauna changed over succeeding millions of years, they supplemented their preserve with prehistoric mammals and early hominids. When Earth's continents shifted circa 50 million BC, the aliens augmented the Land's volcanoes to preserve its tropical status.