On Dec 26, 2004, the Indian Ocean tsunami struck more than a dozen countries, killing over 230,000 people.Twenty years on, many are still picking up the pieces of their lives that were destroyed by the disaster. #indianoceantsunami #tsunami | CNA

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