Italy's Mt. Etna is rumbling again, sending lava down its slopes and an ash cloud into the air. And while no one was hurt in this week’s eruption, it did close down a nearby airport. A live webcam is letting volcano-buffs monitor the lava flows. The largest active volcano in Europe and one of the most active in the world, Etna’s last major eruption was in 1992. Its most violent recorded eruption occurred on March 11, 1669, when lava covered part of the Sicilian town of Catania, killing 15,0000 people.