July 20, 1859 Tsunami: Lontor Island, Banda Sea, Indonesia
A tsunami caused by an earthquake began at Lontor Island, Banda Sea, Indonesia on July 20, 1859. Its effects were recorded at 1 place.
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
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
- July 20, 1859
- Source
- Lontor Island, Banda Sea, Indonesia
- Cause
- Earthquake
- Earthquake
- The earthquake
- Runups recorded
- 1
- Tsunami intensity (Soloviev-Imamura)
- 0
- Waters
- Ocean
- How certain
- Probable tsunami
- Source location
- 4.600° S, 129.900° E
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.
1859, July 20, about 20:00 [local time]. On the west coast of Lonthor Island, there was an underground shock and rumble, like a cannon shot. At first it was thought that the battery at Bandaneira was shooting, but this was a mistake, since after some time, more shots were heard and the sea began to rise slowly above its usual level. Then it fell, and rose again about twice and then returned to the level which existed before the small tsunami. Nothing unusual was noticed on the coast of Neira Island and the islands of the Banda archipelago. (reference #414)
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 |
|---|---|---|---|---|---|---|---|
| Lonthor Island, Banda Islands | Indonesia | 7 | Eyewitness observation of water height |
More
Every tsunami in 1859The 1800sTsunamis of IndonesiaThe earthquakeThis 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 881.