Indonesia Blog PICTURES: Ijen Blue Fire Tour 2019 in May May 16, 2019 webadmin Ijen Crater in the morning. Sulfur Smoke of Ijen Crater It is recommended wearing gas mask to visit Ijen to avoid inhaling sulfur. Stars at Ijen Crater, yes, you can also see the milkyway from Ijen Crater area. *** Getaway Tours, Indonesia Tour Operator