The ground shook in Alaska in March 1964. And shook and shook and shook.
When the earthquake was over, it measured higher in magnitude than any other quake in North American history, more than 130 people were dead, and the resulting tsunami wiped out downtown Crescent City.
Science journalist Henry Fountain pulls many details together for his book The Great Quake: How the Biggest Earthquake in North America Changed Our Understanding of the Planet.
Henry joins us to lay out the facts, with an added bonus: guest host Milt Radford lived through that very quake.