5. The 1976 Tangshan Earthquake
On July 28, 1976, a magnitude 7.5 earthquake struck the city of Tangshan in China, killing an estimated 242,000 people. The city was virtually flattened, with more than 80% of its buildings destroyed in a matter of seconds. Despite being a major industrial hub, the lack of early warning systems and swift response contributed to the staggering death toll.
This earthquake remains one of the deadliest in modern times, highlighting the vulnerability of densely populated areas to seismic events.