October 1, 1134 Tsunami: Southern North Sea
A tsunami of unknown cause began at Southern North Sea on October 1, 1134.
Where the waves reached
The source of the tsunami. No runup with a place is recorded for it.
- Under 1 m
- 1 to 3 m
- 3 to 10 m
- 10 to 30 m
- 30 m and more
- Height not recorded
The tsunami
- Date
- October 1, 1134
- Source
- Southern North Sea
- Cause
- Unknown
- Runups recorded
- 0
- Waters
- Ocean
- How certain
- Very doubtful 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.
Berninghausen (Reference #43) mentions this event, and refers to Mallet and Mallet (Reference #1879): "Middle of the night. The coasts of England and the Netherlands. No land shock felt. The sea rose suddenly with such violence as to inundate the country, and retired to its usual level as suddenly."
More
Every tsunami in 1134The 1100sTsunamis of North SeaThis 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 2026-10-01. NCEI tsunami event 99.