1.4M views · 4.1K shares | Tsunamis are often triggered by volcanic eruptions, earthquakes, landslides, or meteorites—and the waves can spread out thousands of miles. | National Geographic | Facebook

As the twentieth anniversary of the Indian Ocean tsunami approaches, rediscover the story of the worst natural disaster in history with new interviews and never-before-seen archive footage. #TsunamiRaceAgainstTime is now streaming on Disney and Hulu. | National Geographic TV

Biggest Tsunami Caught On Camera | Natural disasters

In 2004, a large earthquake in the Indian Ocean triggered the largest tsunami in recorded history. One of the countries hit by the tsunami was Sri Lanka, where the wave caused one of the worst train disasters in human history when it hit the Queen of the Sea passenger line, which was carrying 1,500 passengers along Sri Lanka's west coast. Watch Destruction Decoded on Wednesdays at 8pm on National Geographic UK. | National Geographic UK