Kawah Ijen Volcano, Java, Indonesia
Volcanos tend to be terrifying, but Kawah Ijen cranks the fear up to another level with its famous blue fires, shooting flames 16 feet into the air, reaching temperatures up to 600 degrees Celsius and emitting its toxic sulphur fumes.
Still, visitors can’t get enough and for those courageous enough to brave the two-hour trek to the crater edge, sights from another world await.
Best viewed in the dead of night, the Blue Fire Volcano emits a startling light as its sulphuric gases emerge from cracks and crevices at high speed, igniting upon contact with the air and illuminating the skies of East Java with a show that must be seen to be believed.
With the toxic fumes hampering breathing and visibility, and the largest highly-acidic crater lake in the world just a stumble away, this isn’t a destination for the nervous. Yet the lights keep shining, and time and again the adventurous return.