Andernach Geyser (German: Geysir Andernach, previously Namedyer Sprudel) is the highest cold-water geyser in the world, reaching heights of 30 to 60 metres. The geyser was first bored in 1903 on the Namedy Peninsula (Namedyer Werth) in the Rhine near Andernach. In 2006 it was turned into a tourist attraction and one of the sights in the volcano park and part of the Geopark Vulkanland Eifel.
In 1903 it is said that a 343-metre-deep borehole was driven on the Namedy peninsula into carbonic acid deposits in order to extract carbon dioxide for mineral water. The reason for boring the hole at this point was that bubbles were seen to be rising in the waters of the old Rhine ox-bow lake. The cold-water geyser was initially erupted and leapt to a height of 40 metres. The "Namedy Fizz" (Namedyer Sprudel) as it was formerly called, as was the resulting bottled mineral water, which was expelled as a result of fizzing carbon dioxide, was used commercially and soon thereafter for tourism. For years, the high fountain was a landmark of the Namedy peninsula. The site suffered from significant damage over the years and in 1957 was put out of operation. Following the upgrade to the B 9 federal highway, the well was closed in 1967 with a valve. In the late 1990s, efforts were made to enable the geyser to become a tourist attraction again, but these conflicted with strict conservation obligations, to which the area had been subject since 1985.
In 1990 ownerside of the peninsula went to the town of Andernach. In 2001 another borehole was drilled at a new location, further from the road, into the gas-permeable rock. Even when the first hole was driven, the geyser jetted back to a height of 40 metres. The well was then fitted with a gate valve again. The Federation for the Environment and Conservation (BUND) presented a case to the Higher Administrative Court of Rhineland-Palatinate to prevent the further development of the geyser for tourism within the nature reserve.. In May 2005 the town of Andernach and the BUND settled outside of court to allow the geyser to be reactivated under certain conservation conditions and for tourism purposes.