As tourists hike around White Island, NZ, there are lots of openings, also known as fumaroles, which have steam and sulfurous gas being emitted out of the volcano landscape. These openings appear as small volcanoes which have recently erupted and when exploring at a close range, gas masks must be worn.
Fumarole emitting sulfurous gas and steam on White Island, an active volcano, Bay of Plenty, East Coast, North Island of New Zealand. The fumarole opening is surrounded by sulphur and various minerals.