Washington, USA 1980
Not many tsunamis have much of an effect on the United States. This was one of the few that did. Most tsunamis are caused by earthquakes, but this one was caused by a landslide. This landslide was caused by the famous eruption of Mt. St Helens. When the volcano erupted, it triggered a massive landslide. Part of this landslide crashed into nearby Spirit Lake and caused a megatsunami 260 meters high. This tsunami destroyed beaches and campgrounds around the lake, and killed all the fish in the lake because of a lack of oxygen from ash and debris. Spirit Lake used to be a popular tourist destination, but has since been closed due to poisonous waters.