At 23:40 on 29 February 1960, an earthquake of only moderate magnitude, around 5.8 to 6, struck directly beneath Agadir on Morocco's Atlantic coast. Because it was so shallow and so close, the damage was catastrophic. About 12,000 people died, roughly a third of the city's population, and some 25,000 were injured. Whole districts collapsed. It remains the deadliest earthquake in Moroccan history and became a textbook case of how building quality, not just magnitude, decides how many people die.
The magnitude figures looked unremarkable. Seismologists later placed the shock at around magnitude 5.8 to 6 on a fault structure running inland from the coast. What made it deadly was geometry: the rupture was shallow and almost directly under a crowded city at night, and it reached the maximum intensity of X.
NOAA's records list the damage. About 90 percent of the old Talborjt quarter was destroyed, along with 70 percent of the new buildings and 20 percent of industrial structures. The old kasbah on the hill above the port crumbled, burying many of its residents.
The ruins were so complete that Morocco chose not to rebuild on the same ground. A new Agadir was laid out a short distance to the south, planned as a modern city. The disaster also led Morocco to adopt earthquake-resistant building standards. Seismologists still cite Agadir when they warn that a moderate quake under a poorly built city can kill more people than a far larger one in open country.