The
1755 Lisbon earthquake, also known as the
Great Lisbon earthquake, occurred in the
Kingdom of Portugal on Saturday, 1 November, the holiday of
All Saints' Day, at around 09:40 local time. In combination with subsequent
fires and a
tsunami (maremoto in
Portuguese), the earthquake almost totally destroyed
Lisbon and adjoining areas.
Seismologists today estimate the Lisbon earthquake had a magnitude in the range 8.5–9.0 on the
moment magnitude scale, with its
epicentre in the
Atlantic Ocean about 200 km (120 mi) west-southwest of
Cape St. Vincent. Estimates place the death toll in Lisbon alone between 10,000 and 100,000 people, making it one of the deadliest earthquakes in history.