Tsunamis in 1065

September 23, 1065 Tsunami: Marmara Sea, Turkey

September 23, 1065 · Probable tsunami

A tsunami caused by an earthquake began at Marmara Sea, Turkey on September 23, 1065. Its effects were recorded at 3 places.

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

The tsunami

Date
September 23, 1065
Source
Marmara Sea, Turkey
Cause
Earthquake
Runups recorded
3
Waters
Ocean
How certain
Probable tsunami

The toll

The record gives no deaths, injuries or damage for this tsunami.

What the record says

NCEI’s account, from the sources it cites.

A destructive earthquake in Constantinople was accompanied by sea waves of huge dimensions that devastated Nicolidea, the Princes Islands, Constantinople, Nicaea. No reference to the tsunami is found in any other catalogue (reference #2130).

Every runup

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

WhereCountryKm from sourceWater height, mInland, mMeasured byFirst wave, UTCDeaths
NicolideaTurkeyEyewitness observation of water height
Princes Islands, Marmara SeaTurkeyEyewitness observation of water height
Istanbul (Constantinople)TurkeyEyewitness observation of water height

More

Every tsunami in 1065The 1000sTsunamis of TurkeyThis day in weather historyAlerts 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 3103.