Since 1738, there have been fifty eruptions, the most powerful of which, in 1877, caused mudflows to travel 60 miles from the volcano and into the Pacific Ocean.  Despite a scare in 2005, the most recent eruption took place in 1904.  The volcano is located to a densely populated part of Ecuador, so if it erupted today, the consequences would be catastrophic.

Cotopaxi, Ecuador

Mount Vesuvius, Italy

It has experienced eight significant explosive eruptions in the past 17,000 years, each accompanied by substantial pyroclastic flows, which are swift-moving streams of volcanic material and highly hot gas that can travel up to 430 miles per hour. A known eruption last occurred in 1944. 

Popocatépetl, Mexico

Only 40 miles southeast of Mexico City, one of the world's largest cities, sits Popocatépetl, the second-highest volcano in North America. There haven't been any significant eruptions in recent memory, but there have been active intervals. Fear of a potential eruption was stoked in 1994 when the volcano released smoke for the first time in 1,000 years.

Mayon Volcano, Philippines

More than 1,200 people were murdered in the Mayon volcano's most powerful eruption in 1814, which is located 8,077 feet above Luzon Island in the Philippines. Eruptions have been documented historically since 1616. In January 2018, after the volcano erupted, forcing enormous ash clouds to rise into the sky, more than 56,000 residents fled the area.

Mount St. Helens, Washington, U.S.

Mount St. Helens is one of the most deadly volcanoes in the United States. It is an active stratovolcano with a height of slightly over 8,000 feet and is situated in Skamania County, Washington, roughly 50 miles northeast of Portland, Oregon. With 57 fatalities, the destruction of 200 square miles of forest, and the deaths of countless of animals, the Mount St. Helens eruption in 1980 was the deadliest and most catastrophic volcanic event in American history.