Imagine standing on a small fishing boat in a quiet Alaskan fjord. It is nearly 10:15 p.m., but the July sun is still hanging low in the sky. Suddenly, the world starts shaking. It’s not just a tremor; it’s a magnitude 7.8 earthquake. Then, you hear a sound like an explosion. You look toward the head of the bay and see the impossible: a wall of water so high it makes the mountains look small.
That was the reality for Howard Ulrich and his seven-year-old son in 1958. They were about to witness the largest tidal wave ever recorded.
Now, scientists usually call these "megatsunamis" rather than tidal waves, mostly because tides have nothing to do with them. But whatever name you use, the numbers from that night in Lituya Bay are basically terrifying. We are talking about a wave that reached a peak height of 1,720 feet.
To put that in perspective, the Empire State Building is only 1,454 feet tall. This wave would have washed over the top of it with room to spare.
The Night the Mountain Fell
Lituya Bay is a T-shaped fjord on the edge of the Fairweather Fault. It’s a beautiful, lonely place, but it's also a geological trap. On July 9, 1958, the earthquake didn't just rattle the ground; it caused a massive chunk of a mountainside to snap off.
Roughly 40 million cubic yards of rock and ice plummeted 3,000 feet straight into the narrow Gilbert Inlet.
Think about that for a second. That is enough rock to fill a football stadium hundreds of times over. When that much mass hits a confined body of water, the water has nowhere to go but up.
The displacement was so violent that the water didn't just ripple out; it "splashed" up the opposite slope of the mountain. It stripped the soil and every single tree off the rock up to that 1,720-foot mark. Geologists later found a "trimline"—a literal line where the old forest ended and bare rock began—marking exactly how high the water reached.
Survivors of the Unsurvivable
There were three boats in the bay that night. Honestly, it's a miracle anyone lived to tell the story.
👉 See also: Is New Jersey Red or Blue State? What the 2026 Shift Really Tells Us
Howard Ulrich was on the Edrie. When he saw the wall of water coming, he didn't have time to pull the anchor. He just let out the chain, put a life jacket on his son, and pointed the bow into the wave. The Edrie was lifted up like a toy. Ulrich later described looking down and seeing the tops of trees far below the hull of his boat. The wave carried them over the land and then, as the water receded, sucked them back into the center of the bay.
The story of the Badger is even wilder. Bill and Vivian Swanson were on board when the wave hit. It picked up their boat and carried them over the La Chaussee Spit—a strip of land at the mouth of the bay. Bill claimed he looked down and saw the forest 80 feet beneath him. The boat eventually foundered, but they managed to escape in a small skiff.
The third boat, the Sunmore, wasn't so lucky. It tried to outrun the wave toward the open ocean, but it was caught and destroyed. No trace of the boat or its crew was ever found.
Why Lituya Bay is Different
You've probably seen footage of the 2004 Indian Ocean tsunami or the 2011 disaster in Japan. Those waves were deadly because they traveled thousands of miles across the open ocean.
The largest tidal wave ever recorded was a different beast. It was a "localized" megatsunami.
- Shape: The narrow, deep fjord acted like a funnel, focusing the energy.
- Mass: The landslide happened in a confined space, pushing the water out with explosive force.
- Speed: Estimates suggest the wave moved through the bay at speeds between 100 and 600 miles per hour.
What Most People Get Wrong
There is a common misconception that the entire bay was covered by a 1,700-foot wall of water. That's not quite right.
The 1,720-foot figure represents the "run-up" height—the highest point the water reached as it slammed into the mountain directly across from the landslide. As the wave traveled down the seven-mile length of the bay, it leveled out. By the time it reached the fishing boats near the entrance, it was still a monstrous 50 to 100 feet high, but it wasn't a skyscraper anymore.
Still, a 100-foot wall of water is enough to ruin anyone's day.
Is It Going to Happen Again?
Geologists like Don Miller, who was one of the first to study the site after the 1958 event, found evidence that this wasn't the first time Lituya Bay had seen such a wave. There were "trimlines" from previous events in 1854, 1899, and 1936.
The bay is basically a giant laboratory for megatsunamis. Because it sits right on a major fault line and has steep, unstable walls, it's almost a certainty that another one will happen eventually.
Actionable Insights for the Future
While you probably aren't planning a fishing trip to a remote Alaskan fjord anytime soon, the lessons from Lituya Bay actually matter for modern safety.
- Understand "Run-up": If you are in a tsunami zone, remember that the height of the wave at sea is not the height it will reach on land. Geography can "magnify" the water's height significantly.
- Landslides Matter: We used to think only undersea earthquakes caused tsunamis. Now we know that landslides—including those in lakes or fjords—can create waves far larger than any ocean-crossing tsunami.
- The "Get High" Rule: In 1958, the survivors only lived because they were either in the middle of the water or high enough to avoid the initial impact. If you feel a long earthquake near a coast, don't wait for a siren. Move to the highest ground possible immediately.
The 1958 megatsunami remains a haunting reminder of how much energy the Earth can release in a single minute. It wasn't just a wave; it was a total reshaping of the landscape. Even today, if you fly over Lituya Bay, you can see the difference in the color of the trees where the forest is still trying to grow back.
It's a scar on the earth that won't go away anytime soon.
For those looking to learn more about the science of these events, checking out the USGS (United States Geological Survey) records on the Fairweather Fault provides a deeper look at why this specific part of Alaska is so volatile. Exploring the 3D simulations created by researchers at the University of Málaga also offers a chilling visual of how that 1,720-foot splash actually looked.
Next Steps:
You can research the "Grand Banks" earthquake of 1929 to see how landslide-generated waves have affected the Atlantic coast, or look into the ongoing monitoring of the Barry Arm glacier in Alaska, where scientists fear a similar megatsunami could be brewing today.