11. The Indian Ocean Tsunami (2004)
On December 26, 2004, a massive undersea earthquake triggered a devastating tsunami that struck multiple countries around the Indian Ocean. The destruction was immediate and overwhelming, claiming the lives of over 230,000 people. Entire communities were wiped out as the world watched in horror, prompting an unprecedented global response and rescue effort. The United Nations highlights how this disaster united nations in grief and action almost overnight.
