Rotorua's spas and geothermal activity have been attracting visitors to the region for centuries and continue to be a highlight.
A myriad of spa options is within easy reach, whether you're after a simple soak in a natural bush-lined thermal stream or hot pool or a full day at a luxuriously-appointed spa complex.
There are two types of mineral waters used for health purposes in Rotorua: “Rachel”, which is alkaline, sulphur water, softening the skin and sedative, and the “Priest”, which is free-acid water. The Rachel waters and mud baths are used to manage rheumatic diseases that required a “softening effect”. The waters are regarded as soothing and sedative, relieving pain and reducing swelling in joints and tissues.
http://www.rotoruanz.com/visit/explore/spa-and-wellness