A giant megatsunami in Alaska created the tallest wave ever recorded in human history.

The tallest wave ever recorded on Earth was not a normal ocean wave and not even a typical tsunami. It was a gigantic megatsunami that struck Lituya Bay in Alaska on July 9, 1958, creating a wave so massive that it reached an astonishing height of approximately 1,720 feet (524 meters).

To put that into perspective, the wave was taller than many skyscrapers and far higher than the Empire State Building’s roof. Even today, scientists consider it one of the most extraordinary natural disasters ever documented.

The event remains the tallest wave ever reliably recorded in human history.

What caused the giant wave in Alaska?

The megatsunami was triggered by a powerful magnitude 7.8 earthquake along the Fairweather Fault in southeastern Alaska.

The earthquake caused an enormous landslide inside the narrow fjord of Lituya Bay. Around 30 million cubic meters of rock and ice suddenly collapsed into the water at incredible speed.

The impact displaced a massive volume of water almost instantly, generating an enormous wall of water that surged across the bay.

Unlike ordinary tsunamis that travel across open oceans after underwater earthquakes, the Lituya Bay event was a localized megatsunami created by a huge landslide in a confined area.

How high was the wave?

Scientists later determined that the wave reached a maximum run-up height of about 1,720 feet (524 meters).

Evidence of the wave could be clearly seen on the surrounding mountainsides, where entire forests had been stripped bare by the force of the water. Even decades later, the scars left behind by the megatsunami remained visible from the air.

The wave destroyed millions of trees and dramatically reshaped the coastline inside the bay.

Despite the unimaginable scale of the event, the remote location prevented an even greater tragedy.

Did anyone survive the megatsunami?

Remarkably, several people survived the disaster.

A few fishing boats were inside Lituya Bay when the wave struck. One boat was lifted high above the treetops before being carried back down by the water. Two people aboard survived.

Another boat disappeared completely and its occupants were never found.

The survivors later described hearing an enormous roar moments before seeing a massive wall of water racing toward them.

What is the difference between a tsunami and a megatsunami?

Although both involve giant waves, tsunamis and megatsunamis are not exactly the same phenomenon.

A tsunami:

• is usually caused by underwater earthquakes,
• spreads across entire ocean basins,
• and often has very long wavelengths.

A megatsunami:

• is typically caused by giant landslides, volcanic collapses or asteroid impacts,
• creates extremely tall localized waves,
• and can produce far greater wave heights near the source.

The Lituya Bay event is considered one of the clearest examples of a megatsunami ever recorded.

Could a wave this large happen again?

Scientists believe another megatsunami is possible under the right geological conditions, although such events are extremely rare.

Areas most vulnerable include:

• steep fjords,
• volcanic islands,
• unstable mountain slopes,
• and regions prone to large earthquakes.

Climate change may also increase certain risks in some areas, especially where melting glaciers destabilize mountain slopes near coastal waters.

Researchers continue to monitor regions in Alaska, Greenland and other polar environments where giant landslides could potentially trigger future megatsunamis.

The deadliest tsunamis in history

While the Lituya Bay megatsunami was the tallest wave ever recorded, it was not the deadliest tsunami in history.

Some of the most catastrophic tsunami disasters include:

Indian Ocean Tsunami (2004)

Triggered by a massive undersea earthquake near Sumatra, this tsunami killed more than 230,000 people across multiple countries.

Japan Tsunami (2011)

The powerful tsunami generated by the Tōhoku earthquake devastated northeastern Japan and triggered the Fukushima nuclear disaster.

Krakatoa Tsunami (1883)

The volcanic eruption of Krakatoa created enormous tsunami waves that destroyed coastal communities in Indonesia.

These events demonstrate how destructive ocean waves can become when geology and water interact violently.

Why scientists still study Lituya Bay today

The 1958 megatsunami remains one of the most important case studies in geology and ocean science.

Researchers continue to analyze:

• the mechanics of giant landslides,
• tsunami behavior in confined bays,
• and the potential risks posed by unstable coastal regions around the world.

The event also helped scientists better understand how extreme natural disasters can reshape landscapes within minutes.

More than 65 years later, Lituya Bay still stands as one of the most dramatic reminders of nature’s power ever witnessed on Earth.