Who Built the Mysterious SOS Sign in Hokkaido?

TL;DR

The person who built the enormous SOS sign near Mount Asahi-dake remains unidentified. Investigators found female human remains, belongings linked to a man named Kenji Iwamura, and a recording of a distressed male voice nearby, but the evidence did not establish who constructed the sign or explain how 19 massive birch logs were moved into place.

Transcript

(eerie music) (static crackling) (suspenseful music) (static crackling) - Monday. (foreboding music) (animals calling) The peak is shrouded in fog. It's the aftermath of one of the most violent storms to hit the area in months. A search helicopter powers through the mist, scouring the region for a pair of hikers from Tokyo who set out the day prior... Read More

Key Insights

• The SOS sign was discovered south of Mount Asahi-dake while rescuers searched for two missing hikers from Tokyo. Although the sign helped direct attention to the area, the rescued men said they had never seen it and had played no role in constructing it.
• The structure was made from 19 cleanly cut birch logs measuring about 16 feet each. It stood in a relatively flat wetland 2.6 miles south of the summit, beyond the mountain's main hiking trail and across terrain involving steep cliffs, dense forest, and the Chubetsu River.
• Human remains were found near the SOS sign alongside a backpack containing a Sony Walkman, four cassette tapes, toothpaste, a bar of soap, and a towel. Wildlife bite marks covered the scattered bones, suggesting that the remains had been exposed in the wilderness before their discovery.
• The initial medical examination identified the remains as belonging to a woman about 5 feet 3 inches tall with Type O blood. Investigators estimated that she was between 20 and 40 years old, had fractures in several locations, and had died one to three years earlier.
• The estimated combined weight of the sign's logs was between 2,850 and 7,600 pounds, based on online wood weight charts cited in the account. That calculation raised doubts that the injured woman could have cut, transported, and arranged all 19 logs without assistance.
• The final cassette recording contained a distressed male voice repeatedly requesting help. The man said he was trapped on a cliff, referred to the place where he first met a helicopter, and explained that deep sasa prevented him from climbing out to safety.
• The male voice spoke as though he were alone and did not mention a female companion. This apparent separation complicated efforts to connect the recording with the woman's remains, even though both pieces of evidence were recovered from the same general location near the SOS sign.
• Kenji Iwamura's license was discovered in a hole hidden beneath foliage about 165 feet north of the SOS sign. Two cameras and a notebook were found with it, giving investigators a possible identity for the recorded man but not conclusively identifying the sign's builder.

Questions & Answers

Q: Who built the mysterious SOS sign near Mount Asahi-dake?

The identity of the person who built the SOS sign was not conclusively established in the account. The two hikers whose rescue led to its discovery denied making it. Female remains were found nearby, while a cassette preserved a distressed male voice and a hidden collection of belongings included Kenji Iwamura's license. None of this evidence definitively proved who constructed the sign.

Q: How was the SOS sign near Mount Asahi-dake discovered?

A search helicopter spotted the sign while looking for two hikers from Tokyo who had disappeared after setting out the previous day. A violent storm had struck the area, fog covered the peak, and daylight was fading. The discovery redirected the search, and rescuers eventually found the hikers emerging from a cave about a mile north of the sign.

Q: Why did the rescued hikers deny making the SOS sign?

The rescued hikers expressed disbelief when the search team praised them for constructing the signal. They directly stated that they had not built a sign and did not know what the rescuers were discussing. Their denial showed that the enormous structure predated their emergency and suggested that another person had become stranded in the remote area at an earlier time.

Q: What was found near the SOS sign in Hokkaido?

Searchers found scattered human remains bearing wildlife bite marks and a backpack containing a Sony Walkman, four cassette tapes, toothpaste, a bar of soap, and a towel. A reporter later discovered another cache about 165 feet north of the sign. That hidden hole contained two cameras, a notebook, and a license belonging to Kenji Iwamura.

Q: What did investigators determine about the human remains?

Examiners from Asahikawa Medical University initially reported that the bones belonged to a woman. They estimated that she was about 5 feet 3 inches tall, had Type O blood, and was between 20 and 40 years old when she died. Her bones had fractures in multiple locations, and her death was placed one to three years before the discovery.

Q: What did the recorded SOS message say?

The male voice repeatedly asked for help and said he was stuck on a cliff. He identified his position as the location where he had first met a helicopter, explained that the sasa was deep, and said he could not climb up. He then asked to be picked up there. The message did not refer to another stranded person.

Q: Why was the size of the SOS sign considered suspicious?

The sign consisted of 19 birch logs, each about 16 feet long. Using online wood weight charts, the account estimated that the complete structure weighed between 2,850 and 7,600 pounds. Moving that quantity of wood, after entering difficult terrain and without any recovered cutting tools, appeared inconsistent with a single injured woman completing the work unaided.

Q: How was Kenji Iwamura connected to the SOS sign incident?

Kenji Iwamura became connected to the case when a reporter found his license in a concealed hole about 165 feet north of the SOS sign. Two cameras and a notebook were recovered from the same location. The discovery suggested that he might have been the distressed man heard on the cassette, but the account did not establish that identification conclusively.

Summary & Key Takeaways

• A helicopter searching near Mount Asahi-dake for two missing hikers spotted a massive SOS sign in a remote wetland. The hikers were rescued about a mile north but denied constructing it. Their confusion prompted investigators to return, suspecting that another stranded person had created the signal and might still need assistance.

• Searchers discovered scattered human remains with wildlife bite marks and a backpack containing a Sony Walkman, four cassette tapes, toothpaste, soap, and a towel. Examiners initially identified the remains as female, estimated an age between 20 and 40, noted several fractures, and placed the death one to three years earlier.

• A cassette contained a distressed male voice asking for rescue from a cliff where deep sasa prevented climbing. Later, belongings found 165 feet north of the sign included cameras, a notebook, and Kenji Iwamura's license. The female remains, male recording, and immense sign created contradictions that investigators could not conclusively resolve.