1. Aira Caldera – Kyushu, Japan
Aira Caldera (姶良カルデラ Aira-Karudera) is a gigantic volcanic caldera in the south of the island of Kyushu, Japan. Its eruption could kill an overwhelming majority of the country’s population.
2. Cumbre Vieja – Canary Islands, Spain
Cumbre Vieja (Spanish: Old Summit) is an active volcanic ridge on the volcanic ocean island of Isla de La Palma in the Canary Islands, Spain. Its next eruption is expected to be within 150 years.
3. Katla – Iceland
Katla is a large volcano in southern Iceland. Katla generally rouses approximately every 80 years, and its last blowout was in 1918.
4. Mount Fuji – Honshu, Japan
Mount Fuji (Fuji-san, 富士山 in Japanese) is the highest volcano and highest peak in Japan. Fuji’s last explosion in 1707 followed an 8.7-magnitude quake.
5. Mount Vesuvius – Gulf of Naples, Italy
Mount Vesuvius is best known for its eruption in AD 79 that led to the burying and destruction of the Roman cities of Pompeii and Herculaneum.
6. Yellowstone Caldera – Wyoming, U.S.A.
The Yellowstone Caldera is the volcanic caldera and supervolcano located in Yellowstone National Park in the United States. This one is so dangerous that its eventual eruption would likely permanently change the face of the planet.