1. The Door to Hell, Turkmenistan:
FOtravel/FOtravel
FOtravel/FOtravel
en.wikipedia.org
The “door” is a huge, gas-filled crater that’s been burning nonstop since it was lit by Soviet scientists in 1971.
2. The Catacombs of Paris:
Adam Baker / CC BY http://2.0 / Via Flickr: atbaker
Matthieu_Photoglovsky/Matthieu_Photoglovsky
Fraser Mummery / CC BY http://2.0 / Flickr: 73014677@N05
The remains of over six million people are found in Paris’ dark, labyrinthine underground tunnels.
3. The cenotes in Mexico:
Luis Javier Sandoval/Luis Javier Sandoval
Hoatzinexp/Hoatzinexp
Luis Javier Sandoval/Luis Javier Sandoval
Natural sinkholes that were literally used for sacrifices by the ancient Mayans.
4. The Tunnel of Love, Ukraine
Alexander Ishchenko/Alexander Ishchenko
Олег Гордиенко/Олег Гордиенко
Олег Гордиенко/Олег Гордиенко
Found deep in the forests of Ukraine, the Tunnel of Love was formerly used to transport industrial goods from a nearby factory.
5. The Richat Structure, Mauritania:
commons.wikimedia.org
en.wikipedia.org
en.wikipedia.org
It was once thought to be the result of an asteroid impact, but it’s now argued to be a deeply eroded geologic dome. The Richat Structure is also known as the Eye of the Sahara and is visible from space.
6. Mount Buzludzha, Bulgaria:
Monodon/Monodon
nikolay100/nikolay100
nikolay100/nikolay100
The former home of the Bulgarian Communist Party is now an abandoned saucer-like structure atop a mountain.
7. The Initiation Wells, Sintra, Portugal:
herraez/herraez
en.wikipedia.org
en.wikipedia.org
Located in the Quinta da Regaleira palace, The Initiation Wells are two underground towers that were once used for ceremonies, including Tarot rites.
8. Aokigahara Forest, Japan:
shutterstock.com
My photos are always part of an adventure./My photos are always part of an adventure.
commons.wikimedia.org
Also known as the Suicide Forest or Sea of Trees. Mount Fuji towers over this eerie forest.
9. Cappadocia, Turkey:
ferar/ferar
ferar/ferar
commons.wikimedia.org
Vast networks of underground chambers and tunnels, some of which bear Byzantine frescoes. Incredible.
10. Masaya Volcano, Nicaragua:
thinkstockphotos.com
AL-Travelpicture/AL-Travelpicture
en.wikipedia.org
This volcanic crater, which has a history of human sacrifice, was referred to as the “Mouth of Hell” by the conquistadors.
11. The tree roots of Meghalaya, India:
uniquely india/uniquely india
uniquely india/uniquely india
Danielrao/Danielrao
A normal wooden bridge would quickly rot in Meghalaya’s subtropical climate — but these bridges consist of ancient tree roots and vines, and they’re very much strong and alive.
12. Kolmanskop, Namibia:
mboersma/mboersma
Sophele/Sophele
Sophele/Sophele
A former diamond mining town in the Namib Desert where geological forces have buried many houses in sand.
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