active danger deposit Geological phenomenon geothermal geothermally hot Mineral natural new zealand outcrop rock Rotorua sulfur sulphur toxic yellow antennae auckland building buildings clouds communications futuristic landmark landmarks point sky Sky Tower spire tall tower towers landscape seep sinkhole vapor vapour vent ewe farming feeding field grass green hill lamb meadow nature peaceful rural sheep slope spring tranquil bubble liquid Mud pool spout steam bathing channel ground Maori village water bleak coast foveaux hills island New rocky scenery sea stark stewart strait tree wild wilderness wind windswept zealand barren horizon Mount Tongariro mountain mountain range Natural landscape peaks plant snow Te Onetapu conservation ecology forest hike lake outdoor ramble river swing track tramp walk waterfall