An ancient tsunami in a Swiss lake triggered by an Alpine landslide suggests that cities now on the lake's shore may face dangers more commonly associated with large oceans, researchers say.
Tsunamis are monster waves reaching more than 100 feet (30 meters) high. Earthquakes often generate them, but landslides can as well — for instance, those occurring in submarine canyons. So, landlocked tsunamis are possible, if lakes get hit by landslides or collapses of the flanks of volcanoes.
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