Beneath the surface of Turkey lies one of the greatest mysteries of the ancient world — vast underground cities carved into the volcanic rock of Cappadocia. In this Spirit in Stone documentary series, we explore the monumental sites of Derinkuyu and Kaymakli, where deep tunnel networks, ventilation shafts, and sealed passages hint at a forgotten chapter of human history. These enormous subterranean cities reach up to 8 levels below the surface and could allegedly house tens of thousands of people. Yet despite their scale and engineering, mainstream explanations remain surprisingly limited. There is no decoration on the walls, no signs of soot from lighting, and no comprehensive sewage or waste system. The tunnels become smaller the deeper we go, some just wide enough for a single person to pass. Why were these structures built — and who were they truly built for? In Derinkuyu, we examine the massive rolling stone doors, narrow passages, and unusual ventilation shafts that descend directly from the surface. Some tunnels appear to have been sealed deliberately — as though someone wanted to close off large parts of the city forever. In Kaymakli, we explore an even more confusing layout, where rooms seem to interlock without obvious planning, and blocked passages suggest ancient events that interrupted construction or forced abandonment. Local legends speak of long, sealed tunnels that once connected these cities — some stretching up to 9 kilometers underground — yet most access points have long since been closed or buried beneath modern settlements. Mainstream archaeology suggests these cities were built during the early Byzantine period as hiding places during times of invasion. But questions remain. Why were they carved so deep into the ground, and why is there no soot or evidence of long-term habitation? Is it possible that these sites are far older than believed — perhaps part of a much larger and now hidden underground system that once stretched across ancient Anatolia? In this playlist, we bring you our long-form expeditions to the underground cities of Turkey — filmed on location, without guides, with full visual access and real-time observations. These are raw explorations of places rarely shown in depth, where the walls themselves seem to whisper a history we’ve only just begun to uncover. 🎥 This is Spirit in Stone. 🔗 https://linktr.ee/spiritinstone 🏷️ Hashtags: #SpiritInStone #AncientTurkey #UndergroundCities #Derinkuyu #Kaymakli #Cappadocia #LostCivilizations #AncientTunnels #SubterraneanWorld #UndergroundStructures #ArchaeologicalMysteries #HiddenHistory #MegalithicTurkey