An earthquake-caused landslide near the head of the nine-mile long bay caused the megatsunami. Only three boats were anchored near the entrance of the bay. One sunk, killing two, but the other boats were able to ride out the smaller waves (and by smaller, I mean around 50 to 100 feet). The megatsunami then moved out to the ocean, where it quickly dissipated.
The survivors’ eyewitness accounts of the wave, coupled with the fact that it destroyed six-foot wide spruce trees that were planted as high as 1,720 feet around the bay (picture above), allowed scientists to pinpoint the height of this record wave. The below 1958 aerial photo shows where vegetation was stripped away in the light-colored areas.
To put this event into perspective, the waves in the 2004 Indian Ocean tsunami – the deadliest in history – were around 35 feet high. It is a good thing Lituya Bay is not a heavily populated area.
If you are interested in learning more about this megatsunami, please go to: http://geology.com/records/biggest-tsunami.shtml.