You may have heard about outer space being referred to as the “final frontier” since so much has already been discovered on Earth. The truth is, though, that it’s a big planet, and there are still amazing things to find right below our feet!

In fact, every day it seems that we find something new that we never thought possible. When loggers arrived at Mt. Pulag in the Philippines during the late 19th century, for instance, they uncovered something inside a cave—something that the locals may have been trying to keep a secret.

Now, the secret is finally out, and it reveals a dark history…

When a team of loggers arrived at the massive and mysterious Mt. Pulag, located in a large and beautiful jungle in the Philippines, during the late 19th century, they found a series of mysterious caves waiting for them.

Philippines-cave-1Anna Kaminski / Flickr

These caves still remain intact today, but as lovely as they may have appear, there’s truly something unsettling about them. One could say that the “sea of clouds” floating around the mountain where they were located serve as a clue to the eeriness to come…

Philippines-Cave-2Anna Kaminski / Flickr

Each and every one of the caves is only accessible through narrow, winding paths and rickety footbridges alongside the mountain. In a lot of ways, it seems like something out of an Indiana Jones film…

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Once brave explorers step inside the enigmatic caves, they’ll uncover something truly creepy. The whole area might look like a movie set, but rest assured that it’s definitely the real deal…

Philippines-Cave-3Karen Easterbrook / Flickr

Those brave enough to explore the frightening cave system can only reach the inside if they are brought there by a tour guide. How many would like to bet that guide always utters prayers for forgiveness before entering?

Philippines-Cave-5Karen Easterbrook / Flickr

The caves themselves hide a horrifying secret—one that the locals likely didn’t want anyone to discover. You can see that there are wooden boxes inside the caves. Can you guess what’s in each of them? That’s right—they’re mummies. In fact, quite a few of the corpses had begun the mummification process long before they’d even died…

Philippines-Cave-6Karen Easterbrook / Flickr

These frightening and fascinating corpses are known as the Fire Mummies, or Ibaloi Mummies, as they were known to the tribe to which they belonged. Their unique mummification process dates as far back as 2000 B.C.

Philippines-Cave-7Karen Easterbrook / Flickr

In this process, when it was becoming increasingly clear that an individual was approaching death, the person who was dying would drink an extremely salty beverage. This would subsequently begin the mummification process…

Philippines-Cave-8Karen Easterbrook / Flickr

After the ailing individual died, they would be washed, put into a seated position, and then placed above a flame. This process was practiced in such a way so that the corpse would dry out instead of becoming cremated and burning into ash.

Philippines-Cave-9Jeno Ortiz / Flickr

Other members of the tribe would additionally contribute to the ritual by blowing tobacco smoke into the deceased tribe member’s mouth, which they believed would help their lost loved one’s insides dry out more quickly.

Philippines-Cave-10Anna Kaminski / Flickr

The entire process took several weeks to complete. That may seem like an unusually long time to work with a dead body, but being that this was such an important ritual in the society, it had to be done with great care.

Philippines-Cave-11tadolo / Flickr

Once each of the bodies was fully mummified, and the corpse was as dried out as it could possibly be, members of the tribe would curl it up so that it took up as little space as possible. The mummy would then be tucked into a wooden box. Families were buried together, but single people were buried alone.

Philippines-Cave-12Karen Easterbrook / Flickr

The Ibaloi people put this practice to an end sometime in the 1500s, after Christian explorers arrived from Spain and imposed their own religious and burial practices. That’s probably why the caves remained untouched for centuries.

Philippines-Cave-13Anna Kaminski / Flickr

Nearly 300 years later, a group of loggers moved into the area and discovered the mummies inside, but unfortunately, they didn’t always respect the remains the way that they should have…

Philippines-Cave-14Karen Easterbrook / Flickr

Eventually, the caves and all of the contents inside of them were named a National Cultural Treasure by the government of the Philippines. Thank goodness they were, because these artifacts are too fascinating and significant to lose!

Philippines-Cave-15karen easterbrook / Flickr

Unfortunately, this didn’t stop vandals from sneaking onto the site and stealing some of the mummies, many of which were sold on the black market. This presented major problems for scientists and historians who were hoping to study the caves.

Philippines-Cave-16Tadolo / Flickr

The mummy of Apo Annu, a tribal chief, was one of those pilfered. Though his body was returned in the 1990s, his cave had undergone severe damage by that time. Many people believed the damage was caused by a curse…

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To this very day, there are still several mummies within the Mount Pulag caves that remain unaccounted for. Some people believe that, while they were human, they may have also been part deity—and they brought upon the curse.

Philippines-Cave-18Anna Kaminski / Flickr

Similarly, many people are still trying to keep the exact location of the cave a secret from the general public. It’s largely to avoid any further disturbances of the nearly 80 remaining mummies.

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The caves are now considered a World Heritage Site by the United Nations Educational, Scientific and Cultural Organization (UNESCO), and many of the descendants of the mummies still visit to perform rituals. Curious travelers can do so as well, provided they find the right tour guide… and if they’re brave enough!

Philippines-Cave-20Tadolo / Flickr

Such a fascinating history! Hopefully these remains stay undisturbed from now on.

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