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Add Yahoo as a preferred source to see more of our stories on Google. A group of hikers look at one of the smoke rings A group of hikers look at one of the smoke rings Europe's most active volcano, ...

Tourists in Italy have been treated to quite the show as Mount Etna, the largest active volcano in Europe, has been blowing spectacular “smoke rings” into the sky since last week. The rare phenomenon, ...

Observations of volcanic vortex rings have been reported at a number of volcanoes over the past several hundred years. The most recent rings emerging from Etna were first spotted last Wednesday.