How Do Ancient ‘Tsunami Stones’ Warn People About Future Disasters in Japan?

  • Tsunamis are fairly common in Japan, primarily because of major earthquakes that tend to hit the area every 100 to 150 years. Because of this, the country implemented advanced countermeasures against future tsunamis and education for disaster preparedness. As a reminder of the devastating impact of tsunamis, tsunami stones came into use. In Aneyoshi, Japan, you can see them dotted along the coastline, reminding generations not to forget the warnings.

    How vulnerable is Japan to tsunamis?

    When a major earthquake occurs under the ocean, it either causes the seabed to rise or sink. This results in a subsequent vertical displacement of water that sends huge waves in every direction, which is called “tsunami.” Tsunamis have inflicted damages on Japan for many years.

    On May 26, 1983, a 10-meter-high tsunami caused by an earthquake in the Sea of Japan killed 13 elementary students. Another earthquake on June 15, 1896, led to a tsunami that killed 22,000 people in various parts of Eastern Japan.

    On July 12, 1993, an earthquake in Hokkaido created waves with a height of 15 meters that hit Okushiri Island. The seawater rushed through narrow valleys, reaching a height of 30 meters and killing more than 200 people.

    The Tsunami Stones

    Such occurrence of disastrous tsunamis led to the carving of the so-called “tsunami stones.” These stones are placed at the exact points of land reached by the tsunami. It serves as a warning for future generations to help them avoid suffering the same catastrophe. Apart from the warning, the stones also advise people at which distance from the shore they would be safe from being swept away by tsunami waves.

    Some of the first tsunami stones are believed to be several years old. An example can be seen in the Aneyoshi Village of Iwate Prefecture. After a large tsunami killed 22,000 people living in the area, residents decided to place the stones. They also moved uphill and carved a special message on the stone stating, “High dwellings are the peace and harmony of our descendants. Remember the calamity of the great tsunamis. Do not build any homes below this point.”

    After the most recent tsunami of 2011, more modern tsunami stones have also been erected. This is especially true in the town of Onagawa in Miyagi Prefecture, which suffered the most damage during the disastrous event.

    Tsunami stones do not only warn people of similar disasters in the future but also commemorate earthquakes and tsunamis that happened in the past. Over time, however, these stone warnings are forgotten, primarily because people place their faith in the massive seawalls that the government built. In places like Aneyoshi, people still heed tsunami warnings.