Hiking in Ijen

East Java is one of the most volcanically active places on earth, and this trip strings two of its set-pieces together over a handful of days. The first is Ijen, whose signature is visible only in the dark: electric-blue flames where sulphuric gas ignites as it escapes the crater. You walk down into the crater at around two in the morning, gas mask on, alongside miners carrying eighty-kilo baskets of raw sulphur up on their shoulders — a working mine, not a show.

The second is Bromo, at the other end of the same day: a small ash cone smoking in the middle of a vast caldera, best seen at sunrise from the rim above as light floods the sand sea around it. The pairing — the underworld at night, the postcard at dawn — is the trip.

Ijen's crater floor closes on gas readings, sometimes for weeks at a time, and masks and guides are required down there. Check conditions before you travel.

Ijen crater access closes on gas readings, sometimes for weeks. Gas masks and guides are required for the crater floor. Re-check conditions before travelling.