Swiss scientists say Geneva and Lausanne remain vulnerable to a tsunami on Lake Geneva, triggered by rockfalls.
They have researched an event nearly 1500 years ago which caused a wall of water up to 13 metres high to engulf the lake shores.
Katrina Kremer, an Earth scientist at the University of Geneva, says not only are Geneva and Lausanne vulnerable today, but also other cities on the edge of mountain lakes and high-sided fjords, because most of people don't know that tsunamis can happen in lakes.
In a letter to the journal Nature Geoscience, Kremer's team report on the 'Tauredunum Event', an episode that occurred in AD 563.
