Ijen Crater boasts of the world's largest acidic volcanic crater lake. To see the blue "fire", one must make a what-felt-like-forever hike up the volcano (steep and stamina challenging slopes if you are not an active person) and a risky descend into the crater. Definitely need a local guide, usually one of the sulphur miners, for this descent. You may also choose to skip seeing the dangerous blue beauty and just enjoy walking around the crater rim at sunrise. #hiking #extreme #volcano #sulphurlake #bluefire