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

Twenty years ago today, on December 26th, 2004, a massive earthquake triggered the deadliest tsunami in recorded history. Multiple waves hit coasts through Southeast Asia, South Asia, Africa and beyond. Both tourists and locals scramble for safety, as the extent of the waves and their destruction become apparent. Discover the power of the human spirit through stories of hope, hardship, and heroism from the 2004 Indian Ocean tsunami. Watch Tsunami: Race Against Time tonight from 5pm, on National