November 2, 1791 Tsunami: Ionian Sea, Greece

Name: November 2, 1791 Tsunami: Ionian Sea, Greece
Start: 1791-11-02
Location: Ionian Sea, Greece

November 2, 1791 · 50 deaths · Questionable tsunami

A tsunami caused by a magnitude 7 earthquake began at Ionian Sea, Greece on November 2, 1791 at 21:00 UTC. Its effects were recorded at 1 place. It killed 50 people, counting the earthquake or eruption that caused it.

Where the waves reached

The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.

Under 1 m
1 to 3 m
3 to 10 m
10 to 30 m
30 m and more
Height not recorded

Tsunami warnings in force

Travel times

How long the first wave took to reach each part of the ocean, one line for each hour up to 24, estimated from the source and the depth of the sea.

The travel times are computed in your browser, which needs JavaScript.

1 to 4 hours
5 to 6 hours
7 to 14 hours
15 hours and more

Computed in your browser the way NOAA’s own travel time maps are: the wave travels at the square root of gravity times the depth, over NOAA’s ETOPO1 depths averaged to a 10 arc-minute grid. Checked against NOAA NCEI’s maps for 21 tsunamis over the first 24 hours, these lines fall within 10 minutes of NCEI’s at half the points compared and within 52 minutes at 9 in 10. They give when the first wave could arrive, not how high it is; bays, harbors and island chains finer than the grid can see it later. Not for use in a warning: see tsunami.gov.

The tsunami

Date: November 2, 1791, 21:00 UTC
Source: Ionian Sea, Greece
Cause: Earthquake
Earthquake: Magnitude 7
Runups recorded: 1
Tsunami intensity (Soloviev-Imamura): 3
Waters: Ocean
How certain: Questionable tsunami
Source location: 37.800° N, 21.000° E

The toll

Deaths: 50 with the earthquake or eruption that caused it
Injuries: 80 with the earthquake or eruption that caused it
Damage: Severe (about $5 to $25 million) with the earthquake or eruption that caused it
Houses destroyed: Many (101 to 1,000) with the earthquake or eruption that caused it

Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.

What the record says

NCEI’s account, from the sources it cites.

1791, November 2. Western Greece, Ionian Islands. 37.8 N, 21 E, earthquake magnitude 7, intensity X, tsunami intensity 3, validity 2. It is possible that a tsunami was observed between the Island of Zakynthos and the continent. (reference #2130)

1791, November 2. Ionian Sea. 37 48 N, 21 00 E, earthquake magnitude 7.0. Strong earthquake at Zakyntos island. Tsunami intensity III, attributed at Zakyntos by Antonopoulos (ref #27) quoting Mallet (ref #497). (reference #4139)

1791, Dec [typo Nov?] 2. Island of Zante. A violent shock followed by others up to the 13th. The most violent agitation occurred in the strait between Zante and the Morea. The first shock threw down many houses, amongst others that of the Austrian Consul-General. A storm of rain, thunder, and lightning raged at the same time. (reference #497)

1791, November 2, 21h. Ionian Sea. 37.8 N, 21 E, earthquake magnitude 7, tsunami magnitude 3. (reference #330)

1791, November 2, 21h. Ionian Sea. 37o45' N, 21o E, magnitude 6.8, intensity X, tsunami intensity 2, reliability 3. (reference #2591)

1791, November 2, 21h. Ionian Sea. 37o45' N, 21o E, magnitude 6.8, intensity X, tsunami intensity 2, reliability 3. (reference #2427)

1791, November 2. Ionian Islands. Between Zante and the mainland (iii). (reference #15)

1791, November 2. Ionian Islands. Between Zante and the mainland (iii) 37.75 N, 21 E, earthquake intensity X. (references #20, #27)

1791, November 2. 38 N 21 E, questionable tsunami (reference #11164, v.2)

Every runup

Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.

Where	Country	Km from source	Water height, m	Inland, m	Measured by	First wave, UTC	Deaths
Island of Zakynthos (Zakinthos)	Greece	9			Eyewitness observation of water height

Every tsunami in 1791 The 1700s Tsunamis of Greece The earthquake This day in weather history Alerts in force

Sources

Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI tsunami event 559.