To reach Ijen volcano, the highlight of the Ijen-Malang-Raung Nature Reserve, set off from the Paltuding post, expect a 90-min walk. A breathtaking sight awaits you: the bare walls of the crater, at the bottom of which lies a milky-green lake, while on the shore a sulphur mine puffs out a thick cloud of smoke... You can go down to the shore of the lake if you protect yourself against the sulphur fumes or remain on the crest and take in the superb view.