On Wednesday 15th January 1919 a tsunami hit Boston, Massachusetts. The wave was 4.5 metres high and swept through the streets at nearly 60 kilometres per hour. Buildings and vehicles were destroyed. People trying to flee were quickly overtaken and drowned.
Final counts put the death toll at twenty-one.
The wave was not sea water but 9.5 million litres of molasses from a nearby industrial accident. For decades afterwards, on a hot day, the streets of Boston would smell like toffee.