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

In the aftermath of the deadliest tsunami in history, many locals and tourists are stranded. Survivors from around the world work together to save lives and are able to achieve some miraculous rescues. However, as the water recedes, the true scale of the disaster becomes clear. Parts three and four of Tsunami: Race Against Time premiere tonight at 9pm on National Geographic UK. | National Geographic UK