Ijen volcano photos: Ijen volcano in East Java is famous for its turquoise acid crater lake and the large sulfur deposits that are being mined by local workers. At night, the scene is illuminated by ghostly blue flames, as sulfur ignites.

Colima volcano photos: This beautiful stratovolcano in western Mexico is one of the most active volcanoes on the American continents. It is known for its often spectacular explosions and sometimes glowing avalanches.