Gerolsteiner bottled water is classified as a mineral water because of the beneficial nutrients it is enriched with. This water becomes enriched with magnesium and calcium as it passes through layers of bedrock deep under the surface of the ground. The calcium and magnesium contained within this water meet a large portion of an average person's daily requirements. The calcium level in this water meets 44 percent of the RDA, while the magnesium meets 29 percent. This makes Gerolsteiner water a healthy choice for quenching the thirst and hydrating the body. The unique underground rock formations that Gerolsteiner passes through are located at the base of a volcano in Western Germany. This area is known as the Volcanic Eifel region. The water is captured at its source more than 200 meters below the surface of the ground where it collects inside natural aquifers. These aquifers help maintain the water's pristine state by protecting it from undesirable impurities.