© iStock

Tyrkiet - Yerebatan Sarnıcı, Istanbul.

© iStock

Sri Lanka - Dambulla grottetempel (Dambullas gyldne tempel).

© iStock

Kina -

Lúdí Yán beliggende i nærheden af Gulin.

© Getty Images 

Malaysia - Batu-grotterne, Gombak, Selangor.

© iStock

Rumænien - Salina Turda saltmine, Durgău-Valea Sărată.

© Shutterstock

Taiwan -

The Dome of Light, Kaohsiung metrostation.

© Shutterstock

Colombia - Zipaquirá saltkatedral. 

© iStock

Polen - Wieliczka saltmine.

© iStock

Egypten - Seti I's grav, Kongernes dal, Luxor.

© Shutterstock

Frankrig - Katakomberne i Paris.

© Shutterstock

Sydafrika -

Cango-grotterne, Oudtshoorn, Vest-Kapprovinsen.

© Shutterstock

Rusland -

Avtovo metrostation, St. Petersborg.

© Shutterstock

New Zealand -

Waitomo Glowworm-grotterne, North Island.

© Shutterstock

Kina - Kejser Qin Shi Huangs mausoleum, Lintong distriktet, Xi'an, Shaanxi-provinsen.

© iStock

Iran - Nooshabads vandreservoir (Nushabad), den underjordiske by Ouee (eller Ouyi).

© iStock

Slovenien - Škocjan-grotterne, Divača.

© iStock

Gibraltar - St. Michaels grotte, Upper Rock Nature Reserve.

© Shutterstock

Sverige - Stadion metrostation, Stockholm.

© iStock

Skotland -

Edinburghs hvælvinger.

© Getty Images

Brasilien - Poço Encantado, Chapada Diamantina National Park.

© iStock

Filippinerne - Puero Princesa Subterranean River National Park.

© Shutterstock

USA -

Cumberlands huler, McMinnville, TN. 

© Getty Images

Det sydlige Australien -

Kirken Sankt Elijah - Serbisk ortodoks kirke, Coober Pedy.

© Getty Images

Island - Vulkanen Thrihnukagigur indefra.

© iStock

USA -

Forestieres underjordiske haver, Fresno, CA.

© Getty Images

Wales -

Llechwedd skiferhuler, Blaenau Ffestiniog, det nordlige Wales.

© Getty Images

USA - Ruby Falls, Chattanooga, TN.

© Shutterstock

Vietnam - Củ Chi-tunnelerne, Ho Chi Minh City.

© Shutterstock

England -

Cabinet War Rooms, Map Room, London.

Se også: Gammel arkitektur, udhugget i sten, som vil føre dig langt tilbage i tiden

© Shutterstock