2004: Devastating tsunami in South Asia, killing 200,000 to 300,000 people

The Indian Ocean tsunami traveled as much as 3,000 miles (nearly 5,000 km) to Africa, arriving with sufficient force to kill people and destroy property. The epicenter of the 9.0 magnitude quake was under the Indian Ocean near the west coast of the Indonesian island of Sumatra, according to the USGS, which monitors earthquakes worldwide.

The Indian Ocean tsunami caused waves as high as 50 feet (15 meters) in some places, according to news reports. But in many other places witnesses described a rapid surging of the ocean, more like an extremely powerful river or a flood than the advance and retreat of giant waves.

Source: National Geographic: The Deadliest Tsunami in History?