The photo above was taken inside the crater of Kawah Ijen volcano on the island of Java, Indonesia . This colorful landscape is one of the most inhospitable places in the world. At upper left sulfuric gases can be seen venting from fractures in the crater. The lake partially filling the crater has a pH of 0.5 -- considered to be one of the most acidic bodies of water in the world. Photo taken on September 13, 2014.