Where did the longest tsunami form?

July 9, 1958: in Lituya Bay, Alaska was caused by a landslide triggered by an 8.3 magnitude earthquake.

The largest Tsunami was formed in Lituya Bay, Alaska

The density of water is 1 g/cm cubed and in order for the pebble to sink its density has to be greater than the density of water and in order for the twig to float its density has to be less than the density of water

Less stable  hope this