Tsunamis

Tsunamis are not like normal wind-generated waves. They have far more energy and can grow to substantial heights (30m) and can travel far inland once they reach the shore. These waves smash into everything in their path and incorporate debris, boats, cars, buildings, trees etc. with the water carrying it all inland until the wave reverses and pulls everything back out to sea.  The tsunami of 2004, shown in the image below affected countries bordering the Indian Ocean and killed more than 225,000 people.