Gerolsteiner Sparkling Mineral Water is a refreshing and naturally carbonated beverage that is sourced from the volcanic Eifel region of Germany. It is a naturally occurring mineral water that is rich in essential minerals such as calcium, magnesium, and bicarbonate.
From Wikipedia
Gerolsteiner Brunnen GmbH & Co. KG (Gerolsteiner) is a leading German mineral water firm with its seat in Gerolstein in the Eifel mountains. The firm is well known for its Gerolsteiner Sprudel brand, a bottled, naturally carbonated mineral water. Gerolsteiner was also the chief sponsor of Team Gerolsteiner a cycling team.