Great Lisbon Earthquake
On All Saints Day 1755, the Portuguese city of Lisbon was hit by a triple disaster - an earthquake, followed by a tsunami and a fire.
One of the most splendid cities in Europe suffered massive damage and thousands of people were killed.
The disaster also led to debate across Europe about whether earthquakes were a natural phenomenon or a message from God.
Witness brings together accounts by British survivors of the earthquake, and hears from Edward Paice, author of Wrath of God - the Great Lisbon Earthquake.
Image: Lisbon before the earthquake (Hulton Archive/Getty Images).