Underground refuges in France

40 Years of Explorations and Studies

Armorican Souterrains of the Iron Age (France)

Underground refuges in Bavaria and Austria

Souterrains and caves in Benin

Underground refuges in Ireland

Underground cities in Cappadocia (Turkey)

Art in quarries (France)

Cave dwellings

Fauna and flora

Mushroom beds (France)

Quarries (creutes) during the First World War

Mine Warfare

Tunnels of Vietnam

Cliff "Cuevas" (Spain)

Underground quarries (France)

Ritual and religious underground passages (France)

Myths, Legends and Literature

Catacombs