Largest steam rings

The active volcano Mount Etna, Sicily, is the tallest and most active volcano in Europe. A complex physical process is causing it to emit huge steam rings, similar to more familiar smoke rings. The steam rings of Mount Etna are around 200 m 650 ft across and can last up to around 10 minutes, as they slowly drift upwards to a height of up to 1000 m 3,300 ft above the volcanic vent.