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12 of the Most Destructive Earthquakes

Alaska: March 28, 1964

The most powerful tremor in U.S. history -- lasting three minutes and measuring 9.2 on the Richter scale -- struck Prince William Sound in Alaska. Only 15 people died in the quake itself, but the resulting tsunami, which reached more than 200 feet high at Valdez inlet, killed 110 more people and caused $311 million in property damage. The city of Anchorage was hit particularly hard, with 30 downtown blocks suffering heavy damage.