1. Cave pool, Santorini, Greece

2. Cave dwelling, Sicily

3. Domus Civita, Italy

4. Caves in Nottingham, England

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5. Hillside Home, Vals, Switzerland

6. Cave homes, Cappadocia, Turkey

7. House Cave, Sacromonte, Spain

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8. Rock houses, Iceland

9. A hogan in Arizona

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10. Vardezia cave city, Georgia

11. Bad Blumau, Austria

12. The Brochs of Coigach, Scotland

13. Beckham Creek Cave Lodge, Parthenon, Arkansas

14. Sala Silvermine, Sweden

15. Village of Kandovan, Iran

16. Nas montanhas de Fafe, Portugal

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17. Dietikon, Switzerland

18. Aloni house, Antiparos Island, Greece

19. Bolton Eco House, England

20. Malator in Druidstone, Wales

21. Rock house

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22. Matmata village, Tunisia

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23. Cave House, Festus, Missouri

24. House of Spiritual Retreat, Seville, Spain

25. Cave Home, Troo, France

26. OUTrial House, Poland

27. Dune House, Atlantic Beach