Karymsky Volcano, Kamchatka Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. Its last eruption was in January 2013. Ash plumes of the volcano reached an altitude of 9800 ft.
Mount Tambora - The biggest volcanic eruption in human history occurred in 1815 on the Indonesian island of Sumbawa, leaving 100,000 dead. There was between six months and three years of steaming and small eruptions after the initial one. Because of the 400 million ton cloud of gas the volcano created, the earth began to cool and 1816 became known as "The Year Without Summer" because of the low temperatures, which killed crops and led to mass starvation,