First English translation of the book that introduced the realm of Hollow Earth. Explores the underground world of Agarttha, sometimes known as Shambhala, a rea

Beliefs in mysterious underworlds are as old as humanity. But the idea that the earth has a hollow interior was first proposed as a scientific theory in 1691 by

Hollow Earth Map Notebook / Journal with lines. Lined notebook with the map of the hollow earth.Hollow world map. There is a theory that the earth is actually h