Great Earthquake of 1755

Today is the 260th anniversary of the deadly earthquake which struck just before 10.00 on All Saints Day 1755. The epicentre was about 200 km into the Atlantic from the south-western tip of Portugal at Cape St. Vincent, and it is estimated to have had a force of 8.5-9ᴼ on the Richter scale. Forty minutes later a massive 20 metre tsunami struck. Immense destruction and loss of life was caused in Lisbon, the Algarve, North Africa, Huelva and Cádiz and the waves caused damage as far away as Ireland, Finland and Brazil. In Jerez the ground shook, buildings collapsed and many churches were badly damaged, though it was spared the tsunami.

Effects of the earthquake in Jerez (foto:masjerez)

In all approaching 100,000 people were killed (2,200 in Cádiz, 2,000 in Huelva) and religious belief could only explain the disaster as God’s wrath at their sins. The extent of the damage and lasting economic problems caused some to look at the event in a more scientific way however, and the Portuguese prime minister, the famous Marqués de Pombal, initiated a study which puts him as the first to investigate seismology.

Blessing of the sea to prevent tsunamis (well that's one way..) at Caleta beach, Cadiz, All Saints Day (foto:lavozdigital)

Now the Spanish Institute for the Reduction of Disasters believes that another earthquake will certainly occur as “all natural disasters will be repeated in time as they obey the laws of Nature.” There was a smaller earthquake out to sea in the Gulf of Cádiz quite recently but thankfully it did no damage. The Institute thinks that the big one could happen every 500-600 years, but is not sure, and is working on ways to mitigate the effects of any such disaster. “The important thing is to learn from history.”