On March 27 , 1964 the Good Friday earthquake struck South-central Alaska , churning the earth for four minutes with a magnitude of 9.2 . The earthquake was one of the most powerful ever recorded and killed 139 people . Most of them were drowned by the tsunamis that tore apart the towns of Valdez and Chenega . Throughout the Prince William Sound region , towns and ports were destroyed and land was uplifted or shoved downward . The uplift destroyed salmon streams , as the fish could no longer jump the various newly created barriers to reach their spawning grounds . Ports at Valdez and Cordova were beyond repair , and the fires destroyed what the mudslides had not . At Valdez , an Alaska Steamship Company ship was lifted by a huge wave over the docks and out to sea , but most hands survived . At Turnagain Arm , off Cook Inlet , the incoming water destroyed trees and caused cabins to sink into the mud . On Kodiak , a tsunami wiped out the villages of Afognak , Old Harbor , and Kaguyak and damaged other communities , while Seward lost its harbor . Despite the extent of the catastrophe , Alaskans rebuilt many of the communities
Good Friday earthquake
1964 Alaska earthquake
History of Alaska