The Mysterious SOS Sign in Japan


An SOS sign, spotted by a rescue helicopter while looking for two lost hikers that went missing on Mt. Asahi ( a.k.a. Mount Asahi-Dake, 旭岳), on the island of Hokkaido, Northern Japan in 1989, was the reason these missing men were saved.

On the afternoon of July 24th, 1989, a police helicopter set out looking for two missing hikers. The day was about to end when the rescue crew spotted this SOS sign a few kilometers away from the mountain trail.

The helicopter landed, and the police officers found the missing hikers coming out of the woods a little north of the SOS sign and they all embarked on the helicopter for the return trip.

Mt. Asahidake, Source of Image: (Licence for Non-Commercial Use)

The rescue operation was successful and everybody was glad it ended so fast with no one’s life in danger. A huge SOS sign made of huge tree logs (up to 5 meters tall, 3m wide), in an open area inside the woods, helped the rescue helicopter locate the two missing hikers.

The Plot Thickens

Daisetsuzan Park -Mount Asahidake, Image from: Wikipedia (Creative Commons licence)

But it was at this point where the story takes an unexpected turn.

The events and details that unfolded have formed one of the most confusing mysteries we have ever witnessed, one that had severe implications to the Japanese society and the emotional stability of Japan’s youth of that era.

A mystery that shook the world.

Back in the helicopter, the two rescued hikers were given food and water and discussing with their rescuers. A police officer pointed out how clever it was to create that SOS sign, as otherwise, the helicopter would have not been able to spot their location.

The two hikers looked at each other in confusion. They replied they didn’t understand what he was talking about.

This reaction was unexpected for the officers and just to be sure, they turned the helicopter, flew again over the area and shown the huge SOS sign to the hikers. This maneuver would require only a minute to head back to the location and fly again over the sign.

Source: Youtube

The hikers were shocked to see the huge SOS sign when they flew over it and explained to the officers this wasn’t them that created it.

A chilling moment of realization for everyone involved, since it became obvious someone else was also down there, asking for help.

It was now clear the huge SOS sign had been created by another person, who was also lost in the woods. The two hikers were just fortunate to venture close to a huge sign they never noticed, and at the same time, lucky enough, the rescue helicopter was scouting the exact same location and noticed the SOS.

These two missing hikers had been rescued by an amazing stroke of luck.

A Second Rescue Operation Begins

Mt. Asahi, Source of Image: (Licence for Non-Commercial Use)

The helicopter flew back to base and a second search and rescue operation was scheduled for the next morning, since it was already getting late for the day.

The following morning, on July 25th, 1989, the second search operation started, this time on the ground. The SOS sign was located four kilometers away from the peak of mount Asahidake and police started searching the area extensively.

The discovery, though, was gruesome, and what everyone was afraid to expect.

Scattered bones lying around the SOS sign area were recovered and,when combined, they completed a human skeleton. The bones also had bite marks on them from wild animals that were possibly inhabiting the woods (presumably foxes).

The bones suggested the victim suffered a tragic fate a long time ago since there was no skin left at all.

These bones were transferred to the Asahikawa Medical University for identification for examination. Initially, the University replied that these bones belonged to a woman with blood type 0. (However, a few days later this information was revised as we will read below).

Just 100 meters away from the SOS sign, the officers also recovered a discarded backpack.

Source: Youtube

This backpack contained various personal items (toothpaste, soap, towel), but the most important one of all was a tape recorder and four tapes that contained theme songs of popular Japanese anime of that era.

Magical Princess Minky Momo, Source: Youtube

The strange discoveries didn’t stop there, though.

This is another part where the story gets even more bizarre than already is, as the police investigators were stunned when they re-winded one of these cassettes and listened to its content.

One of the tapes contains the most shocking discovery of this case.


This is a chilling message that shocked the entire world in 1989, as news reported the story. It doesn’t matter it was in Japanese; it is still the gruesome tone of voice that makes it terrifying.

The translation is below the video, but please heed a warning before you listen to it. This is an extremely unsettling recording because of the harrowing shouts of the unfortunate man while recording.

There is tension and fear in the voice in this recording. Adding the fact that the person didn’t survive is making it worse when listening to it. A desperate cry for help that wasn’t heard until it was too late.

The recording lasts 2:17, however, I’ve only found 16 seconds of it in a single video. The full message translates:

I’m on a cliff and can’t move. S O S. Help me.

I’m on a cliff and can’t move. S O S. Help me.

I’m at the spot where I first saw the helicopter.

The bamboo grass is too deep and I can’t go anywhere.

Please lift me up from here.

The harrowing voice of this man has made children lose their sleep and the whole story shocked the world for the coincidences and the difficulty to connect the details of this mystery.

The message on the tape alone created even more confusion and perplexed the investigation further.

The bones and the tape were found next to the SOS sign, but the person in the recording seems he was trying to explain he was stranded on a cliff and unable to move. Although the bones and the tape recorder were found nowhere near a cliff.

New Questions Arise With the Tape Discovery

  • The bones found had been identified to be woman’s bones, yet the voice in the recording was clearly a man’s.
  • The bones were also found to be fractured in two places (leg and upper body). The man explains he can’t get down the cliff, but the bones were found far from any cliff.
  • How did he cut all these logs on his own, especially when he was hurt (should require extreme physical strength and a tremendous effort to make)?
  • It will also require a tool like an axe or a hatchet to cut the trees, but such an item was never retrieved by the search team.

The bones belonged to a man, not to a woman

For the police, the problem now was that they had identified the bones as belonging to a woman, yet the voice in the tape was a man’s voice. Another request was sent to Asahikawa Medical University to re-examine the case, and new results came out explaining that the bones belonged to a man with blood type-A.

I’ve searched if this was possible for a Medical University to mess so badly with both the bones structure sex results and blood type, and it seems that this can happen often.

We take this as a fact that the bones belong to a man and moving on, but the mystery now comes to the matter that building this SOS sign would require physical strength that a single person with this body structure may not be able to create on his own. Also, there were no tools found that could have been used to cut down the trees.

Random Cliffs , Image from Unsplash (by Simon Berger)

The man, most probably wasn’t hurt when he recorded the tape.

He didn’t mention in the recording that he was hurt and couldn’t walk, but instead he revealed he couldn’t move from the cliff because the bamboo grass was deep.

Apparently, he thought it would be extremely dangerous to climb down the cliff, something that he possibly risked later, and reached the open area where he created the SOS sign.

Although there are reports that the bones found were fractured, we don’t know if this happened before the SOS sign was created, but certainly, on the tape, there is no mention of any injury.

I think, though, that it is more reasonable to consider that the SOS sign was made after the tape was recorded.

He could have been saved if the helicopter searched the area again.

From the tape, we learn the timeline of events.

First, this hiker was stranded in an area difficult to leave and had already spotted a rescue helicopter. Possibly he recorded this message on tape to play it when he would feel exhausted after perhaps enough time passed.

However, he also probably felt the helicopter would not notice him. So he took the risk of descending to lower ground, found a clearing in the forest, and somehow cut these birch trees with an ax he must have been carrying with him.

Although such a tool was never found in the search, that was organized.

After he had finished making the SOS sign, no new search by a helicopter was ever conducted in the region. It could have been a very poor reaction by the rescue operations that didn’t scout the area extensively and didn’t pass from the same spot again.

Maybe the weather conditions didn’t help, and the hiker was unlucky for his SOS message not to be seen by following rescue operations.

New Findings on The Scene — Days Later

On 30th July 1989, Associated Press reports how a journalist for the Japanese TV station HBC found more items hidden in a hole inside a tree, that could also serve as a hiding place for the disappeared man.

Inside the hole, the reporter found two cameras, a notebook, and a driving license on the name: “Kenji Iwamura of Konan City, Aichi Prefecture.”

Kenji Iwamura, Source

Kenji Iwamura was another hiker that was reported missing in the area in 1984 while hiking Mt. Asahi.

That was 5 years earlier.

Authorities contacted Kenji’s parents, and confirmed the objects found were his. Although, as officers reported during questioning about the recording, Kenji’s parents were not sure if the voice belonged to their son.

For how long can such a structure sustain its composition?

Can this SOS sign be sustained for five years without vegetation covering it?

Can this sign still be in a perfectly visible shape after years of rain, heavy snow, and all weather conditions that would apply in the mountainside and remain visible from above for so long?

Or perhaps it was created later by another person. Vegetation, like the bushes that the logs are sitting on, should have covered it during this time..

This video that contains most of the footage saved from the TV coverage from the era.

Unraveling the Mystery

It was reported, that the logs were looking too old, and the investigators also explained how they were partially sunk in the mud.

The police next examined aerial photos of the region and discovered that the SOS sign was observable in aerial photos of 1987, but not in earlier photos taken in 1982. (Source 6:10).

So, we can presume that the missing hiker in 1985 (Kenji Iwamura) created the SOS sign indeed. Although it is a mystery why a tool like an ax wasn’t found together with the rest personal items.

Thoughts and Notes

Asadihake Onsen Trail, Source of Image: (Licence for Non-Commercial Use)

I’ve written about the SOS mystery sign previously, but I didn’t explain the full story. I gave links to two YouTube videos that I now think failed to explain what happened, and instead create even more questions. Sadly, neither Barely Sociable nor KyotoRobato assumptions are plausible. They jumped to early conclusions and didn’t analyze all the facts.

The YouTube video links are these in case you want to watch them:

It also seems the research in these videos was limited and the narrators tried to increase the mystery by claiming it wasn’t possible for the man to climb down the cliffs.

Although, the fact mentioned that Kenji Iwamura’s parents were uncertain about the voice of their son on the cassette recording is worth noticing.

The voice was clear and should have been recognized, but cassette players, as I remember, used to distort the voice in recordings and made it sound heavier. It was barely recognizable who was the person talking in these tapes when we were recording, as the quality was always terrible, especially when someone would be shouting like Kenji did.

Case Closed

Image from Unsplash (by Daniel)

I had to listen to the SOS recording way too many times. It was painful to listen to the disturbing cry for help of this man, especially when I already knew these were some of his last moments.

A few content creators on the internet replicate this mystery trying to make it look unsolvable and increase the tension by hiding details, but the most reasonable explanation is that Kenji Iwamura was the one responsible for the SOS message recorded, and the huge SOS log sign (with great certainty).

Besides the fact that Kenji’s parents weren’t sure about the voice on the recording, the only unclear mystery was how he managed to cut down the birch trees and create the SOS sign. There were no tools found lying around that could have helped him. However, the trees were cut and the SOS sign was still there, so this question already answers itself. Aerial photographs of the area were later found the SOS sign was there at least since 1987, so there is no further question.

Chances suggest that this is the solution to the Japan mystery, and police got the case closed rightfully… this time…

Related Material:


Follow me on: ● ReadCashNoiseCashMediumHiveSteemitVocalMindsTwitterLinkedInRedditemail


DISCLAIMER: All material published in this content, is used for entertainment and educational purposes and falls within the guidelines of fair use. No copyright infringement intended. If you are, or represent, the copyright owner of materials used in this article, and have an issue with the use of said material, please send an email. It illustrates an educational article about the entity that the image represents.

Fair use:

The images illustrate an educational article about the incident described

The images from the incident are low resolution images, and thus not suitable for production of counterfeit goods.

The images are not used in such a way that a reader would be confused into believing that the article is written or authorized by the owner of the image.

They are not replaceable with an uncopyrighted or freely copyrighted image of comparable educational value.

Similar to: link

Support The Content Creators. Subscribe and Like if you enjoyed this story!

Originally published at




Cryptocurrency Writer.

Love podcasts or audiobooks? Learn on the go with our new app.

Recommended from Medium

Gone With the Wind and the Mythologized South

The Modern Art of Cannibalism

Tales of the Cumberlands: A Story-Telling Conference -August 23–26, 2018

2020: The Great American Crack-Up

The function of the age-group in the Igbo pre-colonial society was to?

Anatolian Shepherd Dogs

Index: Book Chapters — Heather C Holmes

Goat Testicles Paid For The World’s Most Powerful Radio Station

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store


Cryptocurrency Writer.

More from Medium

The Fiery Inferno: Four Vinyl I’d Save From My Collection

Vampires and Exorcisms: Catholicism in Modern Horror

How did Michelle McNamara’s obsession with unsolved crimes start?