Rotorua at Wai-O-Tapu thermal area

Mineralised green lake

Silica and sulphur formations
Sulphur cave
Mud pool
Boiling mud

Champagne pool (74 degrees C at the surface and 70m deep)
Edge of Champagne pool (above and below)
see http://www.rotoruanz.co.nz/activities/activity_detail.asp?ID=137

(all photos Canon S5IS)