Isbre is glacier spring water is derived from a source located in the small village of Osa, at the inland end of the Hardanger Fjord in western Norway. The water comes from a glacial-fluvial aquifer, originally formed where two glacially fed rivers entered the fjord at the end of Pleistocene glaciation some 10,000 years ago. These rivers persist in the region today and continue to drain melt waters from the remaining nearby mountain glaciers.
The water is fed into this aquifer through fractures in the high grade metamorphic rocks that compose the 5000 foot peaks that surround the fjord. The cold ambient temperatures of western Norway limit chemical activity which would dissolve these hard silicate rocks. The result is a remarkably pure water with exceptionally low mineralization values, perhaps the lowest mineralization of any bottled natural water.