A hypogeum is an underground structure or subterranean chamber used for various purposes in different cultures throughout history. The term “hypogeum” originates from the Greek words “hypo” (under) and “geos” (earth), emphasizing its underground nature. Hypogea (plural form of hypogeum) can be found in a wide range of civilizations, including ancient Egypt, Rome, Greece, and various prehistoric cultures. These underground spaces were constructed using various techniques and materials, such as stone, mudbrick, or carved into natural rock formations. Hypogea served diverse functions, including burials, religious rituals, storage of goods, and housing. In ancient Egypt, the Valley of the Kings contains numerous hypogea, including the famous tomb of Tutankhamun. The Etruscans in ancient Italy also built impressive underground chamber tombs known as “hypogea.” Hypogea in ancient Rome were often used for burial purposes and were referred to as “hypogea sepulcrales.” In Malta, the Hal Saflieni Hypogeum is an extraordinary prehistoric underground structure that dates back to the Neolithic period. It is a complex system of chambers and passages, believed to have been used for burial rituals and as a place of worship. Hypogea were often elaborately decorated with religious symbols, paintings, and carvings, reflecting the beliefs and practices of the cultures that built them. The study of hypogea provides valuable insights into ancient burial practices, religious beliefs, and architectural techniques. It also offers a glimpse into the cultural and social significance of underground spaces in various historical contexts. The preservation and study of hypogea contribute to our understanding of the complexities of ancient civilizations and their reverence for the underground realm.