Hollow Earth

A concept proposing a hollow or substantially interior Earth, disproven by the 18th century.

The Hollow Earth is a concept proposing that the planet Earth is entirely hollow or contains a substantial interior space. Notably suggested in the late 17th century by Edmond Halley, the notion was later disproven, first tentatively by Pierre Bouguer in 1740, then definitively by Charles Hutton in his Schiehallion experiment around 1774. It was still defended through the mid-19th century, notably by John Cleves Symmes Jr. and J. N. Reynolds, but by this time it was part of popular pseudoscience and no longer a scientifically viable hypothesis. The concept of a hollow Earth still recurs in folklore and as a premise for subterranean fiction, a subgenre of adventure fiction.

Last updated 2026-10-17 from the source article.

Background

The idea of a subterranean land inside the Earth appeared in ancient mythology, folklore and legends. The concept became intertwined with the idea of 'places' of origin or afterlife, such as the Greek underworld, the Nordic Svartálfaheimr, the Christian Hell, and the Jewish Sheol. According to one story from Tibetan Buddhist tradition, there is an ancient city called Shamballa which is located inside the Earth. In Hindu mythology, the underworld is referred to as Patala.

The Angami Naga tribes of India claim that their ancestors emerged in ancient times from a subterranean land inside the Earth. The Taino from Cuba believe their ancestors emerged in ancient times from two caves in a mountain underground. Natives of the Trobriand Islands believe that their ancestors had come from a subterranean land through a cavern hole called 'Obukula'. In Native American mythology, it is said that the ancestors of the Mandan people in ancient times emerged from a subterranean land through a cave on the north side of the Missouri River.

The elders of the Hopi people believe that a Sipapu entrance in the Grand Canyon exists which leads to the underworld. Ancestors of the Inca supposedly came from caves which are located east of Cuzco, Peru.

Did You Know?

Edmond Halley proposed the hollow Earth in 1692 to explain anomalous compass readings.
John Cleves Symmes Jr. suggested the Earth had openings about 2,300 km (1,400 mi) across at both poles.
The Italian writer Dante describes a hollow earth in his 14th-century work Inferno.